From 448ac4ce647b845c4ed4bb203c6599e9c0f8ba09 Mon Sep 17 00:00:00 2001
From: Andrey Lushnikov <lushnikov@chromium.org>
Date: Wed, 21 Jun 2017 07:45:13 -0700
Subject: [PATCH] Reformat codebase into 2-spaces

This patch:
- reformats codebase to use 2-spaces instead of 4. This will
  align the project with other codebases (e.g. DevTools and Lighthouse)
- enables eslint indentation checking

References #19
---
 .eslintrc.js                |    3 +-
 index.js                    |    2 +-
 install.js                  |   28 +-
 lib/Browser.js              |  210 +++----
 lib/Connection.js           |  220 +++----
 lib/Dialog.js               |   86 +--
 lib/FrameManager.js         |  390 ++++++-------
 lib/Page.js                 | 1080 +++++++++++++++++------------------
 lib/Request.js              |  186 +++---
 lib/helpers.js              |   33 +-
 package-lock.json           |  914 +++++++++++++++++++++++++++++
 phantom_shim/FileSystem.js  |  600 +++++++++----------
 phantom_shim/Phantom.js     |  200 +++----
 phantom_shim/System.js      |  158 ++---
 phantom_shim/WebPage.js     |  612 ++++++++++----------
 phantom_shim/WebServer.js   |  114 ++--
 phantom_shim/runner.js      |   92 +--
 phantom_shim/utilities.js   |   24 +-
 test/StaticServer.js        |   54 +-
 test/frame-utils.js         |  108 ++--
 test/golden-utils.js        |  188 +++---
 test/test.js                |  568 +++++++++---------
 utils/ChromiumDownloader.js |  238 ++++----
 utils/check_availability.js |  188 +++---
 yarn.lock                   |    4 +
 25 files changed, 3607 insertions(+), 2693 deletions(-)

diff --git a/.eslintrc.js b/.eslintrc.js
index 7014f72191a..4acbeeb2719 100644
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -100,12 +100,11 @@ module.exports = {
         "no-trailing-spaces": 2,
         "linebreak-style": [ 2, "unix" ],
 
+        "indent": [2, 2, { "SwitchCase": 1, "CallExpression": {"arguments": 2}, "MemberExpression": 2 }],
         /**
          * Disabled, aspirational rules
          */
 
-        "indent": [0, 4, { "SwitchCase": 1, "CallExpression": {"arguments": 2}, "MemberExpression": 2 }],
-
         // brace-style is disabled, as eslint cannot enforce 1tbs as default, but allman for functions
         "brace-style": [0, "allman", { "allowSingleLine": true }],
 
diff --git a/index.js b/index.js
index 51451f9ae28..f9e23c37c19 100644
--- a/index.js
+++ b/index.js
@@ -15,5 +15,5 @@
  */
 
 module.exports = {
-    Browser: require('./lib/Browser')
+  Browser: require('./lib/Browser')
 };
diff --git a/install.js b/install.js
index 588a393faca..0d6b7f0a5e2 100644
--- a/install.js
+++ b/install.js
@@ -20,28 +20,26 @@ var ProgressBar = require('progress');
 
 // Do nothing if the revision is already downloaded.
 if (Downloader.revisionInfo(Downloader.currentPlatform(), revision))
-    return;
+  return;
 
 Downloader.downloadRevision(Downloader.currentPlatform(), revision, onProgress)
-    .catch(error => {
-        console.error('Download failed: ' + error.message);
-    });
+    .catch(error => console.error('Download failed: ' + error.message));
 
 var progressBar = null;
 function onProgress(bytesTotal, delta) {
-    if (!progressBar) {
-        progressBar = new ProgressBar(`Downloading Chromium - ${toMegabytes(bytesTotal)} [:bar] :percent :etas `, {
-            complete: '=',
-            incomplete: ' ',
-            width: 20,
-            total: bytesTotal,
-        });
-    }
-    progressBar.tick(delta);
+  if (!progressBar) {
+    progressBar = new ProgressBar(`Downloading Chromium - ${toMegabytes(bytesTotal)} [:bar] :percent :etas `, {
+      complete: '=',
+      incomplete: ' ',
+      width: 20,
+      total: bytesTotal,
+    });
+  }
+  progressBar.tick(delta);
 }
 
 function toMegabytes(bytes) {
-    var mb = bytes / 1024 / 1024;
-    return (Math.round(mb * 10) / 10) + ' Mb';
+  var mb = bytes / 1024 / 1024;
+  return (Math.round(mb * 10) / 10) + ' Mb';
 }
 
diff --git a/lib/Browser.js b/lib/Browser.js
index e6452462706..16b665d6538 100644
--- a/lib/Browser.js
+++ b/lib/Browser.js
@@ -26,125 +26,125 @@ var CHROME_PROFILE_PATH = path.resolve(__dirname, '..', '.dev_profile');
 var browserId = 0;
 
 var DEFAULT_ARGS = [
-    '--disable-background-timer-throttling',
-    '--no-first-run',
+  '--disable-background-timer-throttling',
+  '--no-first-run',
 ];
 
 class Browser {
-    /**
-     * @param {(!Object|undefined)} options
-     */
-    constructor(options) {
-        options = options || {};
-        ++browserId;
-        this._userDataDir = CHROME_PROFILE_PATH + browserId;
-        this._remoteDebuggingPort = 9227;
-        if (typeof options.remoteDebuggingPort === 'number')
-            this._remoteDebuggingPort = options.remoteDebuggingPort;
-        this._chromeArguments = DEFAULT_ARGS.concat([
-            `--user-data-dir=${this._userDataDir}`,
-            `--remote-debugging-port=${this._remoteDebuggingPort}`,
-        ]);
-        if (typeof options.headless !== 'boolean' || options.headless) {
-            this._chromeArguments.push(...[
-                `--headless`,
-                `--disable-gpu`,
-            ]);
-        }
-        if (typeof options.executablePath === 'string') {
-            this._chromeExecutable = options.executablePath;
-        } else {
-            var chromiumRevision = require('../package.json').puppeteer.chromium_revision;
-            var revisionInfo = Downloader.revisionInfo(Downloader.currentPlatform(), chromiumRevision);
-            console.assert(revisionInfo, 'Chromium revision is not downloaded. Run npm install');
-            this._chromeExecutable = revisionInfo.executablePath;
-        }
-        if (Array.isArray(options.args))
-            this._chromeArguments.push(...options.args);
-        this._terminated = false;
-        this._chromeProcess = null;
+  /**
+   * @param {(!Object|undefined)} options
+   */
+  constructor(options) {
+    options = options || {};
+    ++browserId;
+    this._userDataDir = CHROME_PROFILE_PATH + browserId;
+    this._remoteDebuggingPort = 9227;
+    if (typeof options.remoteDebuggingPort === 'number')
+      this._remoteDebuggingPort = options.remoteDebuggingPort;
+    this._chromeArguments = DEFAULT_ARGS.concat([
+      `--user-data-dir=${this._userDataDir}`,
+      `--remote-debugging-port=${this._remoteDebuggingPort}`,
+    ]);
+    if (typeof options.headless !== 'boolean' || options.headless) {
+      this._chromeArguments.push(...[
+        `--headless`,
+        `--disable-gpu`,
+      ]);
     }
-
-    /**
-     * @return {!Promise<!Page>}
-     */
-    async newPage() {
-        await this._ensureChromeIsRunning();
-        if (!this._chromeProcess || this._terminated)
-            throw new Error('ERROR: this chrome instance is not alive any more!');
-        var client = await Connection.create(this._remoteDebuggingPort);
-        var page = await Page.create(client);
-        return page;
+    if (typeof options.executablePath === 'string') {
+      this._chromeExecutable = options.executablePath;
+    } else {
+      var chromiumRevision = require('../package.json').puppeteer.chromium_revision;
+      var revisionInfo = Downloader.revisionInfo(Downloader.currentPlatform(), chromiumRevision);
+      console.assert(revisionInfo, 'Chromium revision is not downloaded. Run npm install');
+      this._chromeExecutable = revisionInfo.executablePath;
     }
+    if (Array.isArray(options.args))
+      this._chromeArguments.push(...options.args);
+    this._terminated = false;
+    this._chromeProcess = null;
+  }
 
-    /**
-     * @param {!Page} page
-     */
-    async closePage(page) {
-        if (!this._chromeProcess || this._terminated)
-            throw new Error('ERROR: this chrome instance is not running');
-        await page.close();
-    }
+  /**
+   * @return {!Promise<!Page>}
+   */
+  async newPage() {
+    await this._ensureChromeIsRunning();
+    if (!this._chromeProcess || this._terminated)
+      throw new Error('ERROR: this chrome instance is not alive any more!');
+    var client = await Connection.create(this._remoteDebuggingPort);
+    var page = await Page.create(client);
+    return page;
+  }
 
-    /**
-     * @return {string}
-     */
-    async version() {
-        await this._ensureChromeIsRunning();
-        var version = await Connection.version(this._remoteDebuggingPort);
-        return version.Browser;
-    }
+  /**
+   * @param {!Page} page
+   */
+  async closePage(page) {
+    if (!this._chromeProcess || this._terminated)
+      throw new Error('ERROR: this chrome instance is not running');
+    await page.close();
+  }
 
-    async _ensureChromeIsRunning() {
-        if (this._chromeProcess)
-            return;
-        this._chromeProcess = childProcess.spawn(this._chromeExecutable, this._chromeArguments, {});
-        var stderr = '';
-        this._chromeProcess.stderr.on('data', data => stderr += data.toString('utf8'));
-        // Cleanup as processes exit.
-        process.on('exit', () => this._chromeProcess.kill());
-        this._chromeProcess.on('exit', () => {
-            this._terminated = true;
-            removeRecursive(this._userDataDir);
-        });
+  /**
+   * @return {string}
+   */
+  async version() {
+    await this._ensureChromeIsRunning();
+    var version = await Connection.version(this._remoteDebuggingPort);
+    return version.Browser;
+  }
 
-        await waitForChromeResponsive(this._remoteDebuggingPort, () => !this._terminated);
-        if (this._terminated)
-            throw new Error('Failed to launch chrome! ' + stderr);
-    }
+  async _ensureChromeIsRunning() {
+    if (this._chromeProcess)
+      return;
+    this._chromeProcess = childProcess.spawn(this._chromeExecutable, this._chromeArguments, {});
+    var stderr = '';
+    this._chromeProcess.stderr.on('data', data => stderr += data.toString('utf8'));
+    // Cleanup as processes exit.
+    process.on('exit', () => this._chromeProcess.kill());
+    this._chromeProcess.on('exit', () => {
+      this._terminated = true;
+      removeRecursive(this._userDataDir);
+    });
 
-    close() {
-        if (!this._chromeProcess)
-            return;
-        this._chromeProcess.kill();
-    }
+    await waitForChromeResponsive(this._remoteDebuggingPort, () => !this._terminated);
+    if (this._terminated)
+      throw new Error('Failed to launch chrome! ' + stderr);
+  }
+
+  close() {
+    if (!this._chromeProcess)
+      return;
+    this._chromeProcess.kill();
+  }
 }
 
 module.exports = Browser;
 
 function waitForChromeResponsive(remoteDebuggingPort, shouldWaitCallback) {
-    var fulfill;
-    var promise = new Promise(x => fulfill = x);
-    var options = {
-        method: 'GET',
-        host: 'localhost',
-        port: remoteDebuggingPort,
-        path: '/json/list'
-    };
-    var probeTimeout = 100;
-    sendRequest();
-    return promise;
+  var fulfill;
+  var promise = new Promise(x => fulfill = x);
+  var options = {
+    method: 'GET',
+    host: 'localhost',
+    port: remoteDebuggingPort,
+    path: '/json/list'
+  };
+  var probeTimeout = 100;
+  sendRequest();
+  return promise;
 
-    function sendRequest() {
-        var req = http.request(options, res => {
-            fulfill();
-        });
-        req.on('error', e => {
-            if (shouldWaitCallback())
-                setTimeout(sendRequest, probeTimeout);
-            else
-                fulfill();
-        });
-        req.end();
-    }
+  function sendRequest() {
+    var req = http.request(options, res => {
+      fulfill();
+    });
+    req.on('error', e => {
+      if (shouldWaitCallback())
+        setTimeout(sendRequest, probeTimeout);
+      else
+        fulfill();
+    });
+    req.end();
+  }
 }
diff --git a/lib/Connection.js b/lib/Connection.js
index cc1735a131e..25f924598da 100644
--- a/lib/Connection.js
+++ b/lib/Connection.js
@@ -20,90 +20,90 @@ var http = require('http');
 const COMMAND_TIMEOUT = 10000;
 
 class Connection extends EventEmitter {
-    /**
-     * @param {number} port
-     * @param {string} pageId
-     * @param {!WebSocket} ws
-     */
-    constructor(port, pageId, ws) {
-        super();
-        this._port = port;
-        this._pageId = pageId;
-        this._lastId = 0;
-        /** @type {!Map<number, {resolve: function(*), reject: function(*), method: string}>}*/
-        this._callbacks = new Map();
+  /**
+   * @param {number} port
+   * @param {string} pageId
+   * @param {!WebSocket} ws
+   */
+  constructor(port, pageId, ws) {
+    super();
+    this._port = port;
+    this._pageId = pageId;
+    this._lastId = 0;
+    /** @type {!Map<number, {resolve: function(*), reject: function(*), method: string}>}*/
+    this._callbacks = new Map();
 
-        this._ws = ws;
-        this._ws.on('message', this._onMessage.bind(this));
-        this._ws.on('close', this._onClose.bind(this));
+    this._ws = ws;
+    this._ws.on('message', this._onMessage.bind(this));
+    this._ws.on('close', this._onClose.bind(this));
+  }
+
+  /**
+   * @param {string} method
+   * @param {(!Object|undefined)} params
+   * @return {!Promise<?Object>}
+   */
+  send(method, params = {}) {
+    var id = ++this._lastId;
+    var message = JSON.stringify({id, method, params});
+    this._ws.send(message);
+    return new Promise((resolve, reject) => {
+      this._callbacks.set(id, {resolve, reject, method});
+    });
+  }
+
+  /**
+   * @param {string} message
+   */
+  _onMessage(message) {
+    var object = JSON.parse(message);
+    if (object.id && this._callbacks.has(object.id)) {
+      var callback = this._callbacks.get(object.id);
+      this._callbacks.delete(object.id);
+      if (object.error)
+        callback.reject(new Error(`Protocol error (${callback.method}): ${object.error.message}`));
+      else
+        callback.resolve(object.result);
+    } else {
+      console.assert(!object.id);
+      this.emit(object.method, object.params);
     }
+  }
 
-    /**
-     * @param {string} method
-     * @param {(!Object|undefined)} params
-     * @return {!Promise<?Object>}
-     */
-    send(method, params = {}) {
-        var id = ++this._lastId;
-        var message = JSON.stringify({id, method, params});
-        this._ws.send(message);
-        return new Promise((resolve, reject) => {
-            this._callbacks.set(id, {resolve, reject, method});
-        });
-    }
+  _onClose() {
+    this._ws.removeAllListeners();
+    this._ws.close();
+  }
 
-    /**
-     * @param {string} message
-     */
-    _onMessage(message) {
-        var object = JSON.parse(message);
-        if (object.id && this._callbacks.has(object.id)) {
-            var callback = this._callbacks.get(object.id);
-            this._callbacks.delete(object.id);
-            if (object.error)
-                callback.reject(new Error(`Protocol error (${callback.method}): ${object.error.message}`));
-            else
-                callback.resolve(object.result);
-        } else {
-            console.assert(!object.id);
-            this.emit(object.method, object.params);
-        }
-    }
+  /**
+   * @return {!Promise}
+   */
+  async dispose() {
+    await runJsonCommand(this._port, `close/${this._pageId}`);
+  }
 
-    _onClose() {
-        this._ws.removeAllListeners();
-        this._ws.close();
-    }
+  /**
+   * @param {number} port
+   * @return {!Promise<!Connection>}
+   */
+  static async create(port) {
+    var newTab = await runJsonCommand(port, 'new');
+    var url = newTab.webSocketDebuggerUrl;
 
-    /**
-     * @return {!Promise}
-     */
-    async dispose() {
-        await runJsonCommand(this._port, `close/${this._pageId}`);
-    }
+    return new Promise((resolve, reject) => {
+      var ws = new WebSocket(url, { perMessageDeflate: false });
+      ws.on('open', () => resolve(new Connection(port, newTab.id, ws)));
+      ws.on('error', reject);
+    });
+  }
 
-    /**
-     * @param {number} port
-     * @return {!Promise<!Connection>}
-     */
-    static async create(port) {
-        var newTab = await runJsonCommand(port, 'new');
-        var url = newTab.webSocketDebuggerUrl;
-
-        return new Promise((resolve, reject) => {
-            var ws = new WebSocket(url, { perMessageDeflate: false });
-            ws.on('open', () => resolve(new Connection(port, newTab.id, ws)));
-            ws.on('error', reject);
-        });
-    }
-
-    /**
-     * @param {number} port
-     * @return {!Promise<!Object>}
-     */
-    static version(port) {
-        return runJsonCommand(port, 'version');
-    }
+  /**
+   * @param {number} port
+   * @return {!Promise<!Object>}
+   */
+  static version(port) {
+    return runJsonCommand(port, 'version');
+  }
 }
 
 /**
@@ -112,41 +112,41 @@ class Connection extends EventEmitter {
  * @return {!Promise<!Object>}
  */
 function runJsonCommand(port, command) {
-    var request = http.get({
-        hostname: 'localhost',
-        port: port,
-        path: '/json/' + command
-    }, onResponse);
-    request.setTimeout(COMMAND_TIMEOUT, onTimeout);
-    var resolve, reject;
-    return new Promise((res, rej) => { resolve = res; reject = rej; });
+  var request = http.get({
+    hostname: 'localhost',
+    port: port,
+    path: '/json/' + command
+  }, onResponse);
+  request.setTimeout(COMMAND_TIMEOUT, onTimeout);
+  var resolve, reject;
+  return new Promise((res, rej) => { resolve = res; reject = rej; });
 
-    function onResponse(response) {
-        var data = '';
-        response.on('data', chunk => data += chunk);
-        response.on('end', () => {
-            if (response.statusCode !== 200) {
-                reject(new Error(`Protocol JSON API error (${command}), status: ${response.statusCode}`));
-                return;
-            }
-            // In the case of 'close' & 'activate' Chromium returns a string rather than JSON: goo.gl/7v27xD
-            if (data === 'Target is closing' || data === 'Target activated') {
-                resolve({message: data});
-                return;
-            }
-            try {
-              resolve(JSON.parse(data));
-            } catch (e) {
-              reject(e);
-            }
-        });
-    }
+  function onResponse(response) {
+    var data = '';
+    response.on('data', chunk => data += chunk);
+    response.on('end', () => {
+      if (response.statusCode !== 200) {
+        reject(new Error(`Protocol JSON API error (${command}), status: ${response.statusCode}`));
+        return;
+      }
+      // In the case of 'close' & 'activate' Chromium returns a string rather than JSON: goo.gl/7v27xD
+      if (data === 'Target is closing' || data === 'Target activated') {
+        resolve({message: data});
+        return;
+      }
+      try {
+        resolve(JSON.parse(data));
+      } catch (e) {
+        reject(e);
+      }
+    });
+  }
 
-    function onTimeout() {
-        request.abort();
-        // Reject on error with code specifically indicating timeout in connection setup.
-        reject(new Error('Timeout waiting for initial Debugger Protocol connection.'));
-    }
+  function onTimeout() {
+    request.abort();
+    // Reject on error with code specifically indicating timeout in connection setup.
+    reject(new Error('Timeout waiting for initial Debugger Protocol connection.'));
+  }
 }
 
 module.exports = Connection;
diff --git a/lib/Dialog.js b/lib/Dialog.js
index db859a370df..af2cbf34d15 100644
--- a/lib/Dialog.js
+++ b/lib/Dialog.js
@@ -15,55 +15,55 @@
  */
 
 class Dialog {
-    /**
-     * @param {!Connection} client
-     * @param {!Dialog.Type} type
-     * @param {string} message
-     */
-    constructor(client, type, message) {
-        this._client = client;
-        this.type = type;
-        this._message = message;
-        this._handled = false;
-    }
+  /**
+   * @param {!Connection} client
+   * @param {!Dialog.Type} type
+   * @param {string} message
+   */
+  constructor(client, type, message) {
+    this._client = client;
+    this.type = type;
+    this._message = message;
+    this._handled = false;
+  }
 
-    /**
-     * @return {string}
-     */
-    message() {
-        return this._message;
-    }
+  /**
+   * @return {string}
+   */
+  message() {
+    return this._message;
+  }
 
-    /**
-     * @param {string=} promptText
-     * @return {!Promise}
-     */
-    async accept(promptText) {
-        console.assert(!this._handled, 'Cannot accept dialog which is already handled!');
-        this._handled = true;
-        await this._client.send('Page.handleJavaScriptDialog', {
-            accept: true,
-            promptText: promptText
-        });
-    }
+  /**
+   * @param {string=} promptText
+   * @return {!Promise}
+   */
+  async accept(promptText) {
+    console.assert(!this._handled, 'Cannot accept dialog which is already handled!');
+    this._handled = true;
+    await this._client.send('Page.handleJavaScriptDialog', {
+      accept: true,
+      promptText: promptText
+    });
+  }
 
-    /**
-     * @return {!Promise}
-     */
-    async dismiss() {
-        console.assert(!this._handled, 'Cannot dismiss dialog which is already handled!');
-        this._handled = true;
-        await this._client.send('Page.handleJavaScriptDialog', {
-            accept: false
-        });
-    }
+  /**
+   * @return {!Promise}
+   */
+  async dismiss() {
+    console.assert(!this._handled, 'Cannot dismiss dialog which is already handled!');
+    this._handled = true;
+    await this._client.send('Page.handleJavaScriptDialog', {
+      accept: false
+    });
+  }
 }
 
 Dialog.Type = {
-    Alert: 'alert',
-    BeforeUnload: 'beforeunload',
-    Confirm: 'confirm',
-    Prompt: 'prompt'
+  Alert: 'alert',
+  BeforeUnload: 'beforeunload',
+  Confirm: 'confirm',
+  Prompt: 'prompt'
 };
 
 module.exports = Dialog;
diff --git a/lib/FrameManager.js b/lib/FrameManager.js
index 6e0e82755c0..8763229aa4a 100644
--- a/lib/FrameManager.js
+++ b/lib/FrameManager.js
@@ -17,229 +17,229 @@
 var EventEmitter = require('events');
 
 class FrameManager extends EventEmitter {
-    /**
-     * @param {!Connection} client
-     * @return {!FrameManager}
-     */
-    static async create(client) {
-        var mainFramePayload = await client.send('Page.getResourceTree');
-        return new FrameManager(client, mainFramePayload.frameTree);
+  /**
+   * @param {!Connection} client
+   * @return {!FrameManager}
+   */
+  static async create(client) {
+    var mainFramePayload = await client.send('Page.getResourceTree');
+    return new FrameManager(client, mainFramePayload.frameTree);
+  }
+
+  /**
+   * @param {!Connection} client
+   * @param {!Object} frameTree
+   */
+  constructor(client, frameTree) {
+    super();
+    this._client = client;
+    /** @type {!Map<string, !Frame>} */
+    this._frames = new Map();
+    this._mainFrame = this._addFramesRecursively(null, frameTree);
+
+    this._client.on('Page.frameAttached', event => this._frameAttached(event.frameId, event.parentFrameId));
+    this._client.on('Page.frameNavigated', event => this._frameNavigated(event.frame));
+    this._client.on('Page.frameDetached', event => this._frameDetached(event.frameId));
+  }
+
+  /**
+   * @return {!Frame}
+   */
+  mainFrame() {
+    return this._mainFrame;
+  }
+
+  /**
+   * @return {!Array<!Frame>}
+   */
+  frames() {
+    return Array.from(this._frames.values());
+  }
+
+  /**
+   * @param {string} frameId
+   * @param {?string} parentFrameId
+   * @return {?Frame}
+   */
+  _frameAttached(frameId, parentFrameId) {
+    if (this._frames.has(frameId))
+      return;
+
+    if (!parentFrameId) {
+      // Navigation to the new backend process.
+      this._navigateFrame(this._mainFrame, frameId, null);
+      return;
     }
+    var parentFrame = this._frames.get(parentFrameId);
+    var frame = new Frame(parentFrame, frameId, null);
+    this._frames.set(frame._id, frame);
+    this.emit(FrameManager.Events.FrameAttached, frame);
+  }
 
-    /**
-     * @param {!Connection} client
-     * @param {!Object} frameTree
-     */
-    constructor(client, frameTree) {
-        super();
-        this._client = client;
-        /** @type {!Map<string, !Frame>} */
-        this._frames = new Map();
-        this._mainFrame = this._addFramesRecursively(null, frameTree);
-
-        this._client.on('Page.frameAttached', event => this._frameAttached(event.frameId, event.parentFrameId));
-        this._client.on('Page.frameNavigated', event => this._frameNavigated(event.frame));
-        this._client.on('Page.frameDetached', event => this._frameDetached(event.frameId));
+  /**
+   * @param {!Object} framePayload
+   */
+  _frameNavigated(framePayload) {
+    var frame = this._frames.get(framePayload.id);
+    if (!frame) {
+      // Simulate missed "frameAttached" for a main frame navigation to the new backend process.
+      console.assert(!framePayload.parentId, 'Main frame shouldn\'t have parent frame id.');
+      frame = this._mainFrame;
     }
+    this._navigateFrame(frame, framePayload.id, framePayload);
+  }
 
-    /**
-     * @return {!Frame}
-     */
-    mainFrame() {
-        return this._mainFrame;
-    }
+  /**
+   * @param {string} frameId
+   */
+  _frameDetached(frameId) {
+    var frame = this._frames.get(frameId);
+    if (frame)
+      this._removeFramesRecursively(frame);
+  }
 
-    /**
-     * @return {!Array<!Frame>}
-     */
-    frames() {
-        return Array.from(this._frames.values());
-    }
+  /**
+   * @param {!Frame} frame
+   * @param {string} newFrameId
+   * @param {?Object} newFramePayload
+   */
+  _navigateFrame(frame, newFrameId, newFramePayload) {
+    // Detach all child frames first.
+    for (var child of frame.childFrames())
+      this._removeFramesRecursively(child);
+    this._frames.delete(frame._id, frame);
+    frame._id = newFrameId;
+    frame._adoptPayload(newFramePayload);
+    this._frames.set(newFrameId, frame);
+    this.emit(FrameManager.Events.FrameNavigated, frame);
+  }
 
-    /**
-     * @param {string} frameId
-     * @param {?string} parentFrameId
-     * @return {?Frame}
-     */
-    _frameAttached(frameId, parentFrameId) {
-        if (this._frames.has(frameId))
-            return;
+  /**
+   * @param {?Frame} parentFrame
+   * @param {!Object} frameTreePayload
+   * @return {!Frame}
+   */
+  _addFramesRecursively(parentFrame, frameTreePayload) {
+    var framePayload = frameTreePayload.frame;
+    var frame = new Frame(parentFrame, framePayload.id, framePayload);
+    this._frames.set(frame._id, frame);
 
-        if (!parentFrameId) {
-            // Navigation to the new backend process.
-            this._navigateFrame(this._mainFrame, frameId, null);
-            return;
-        }
-        var parentFrame = this._frames.get(parentFrameId);
-        var frame = new Frame(parentFrame, frameId, null);
-        this._frames.set(frame._id, frame);
-        this.emit(FrameManager.Events.FrameAttached, frame);
-    }
+    for (var i = 0; frameTreePayload.childFrames && i < frameTreePayload.childFrames.length; ++i)
+      this._addFramesRecursively(frame, frameTreePayload.childFrames[i]);
+    return frame;
+  }
 
-    /**
-     * @param {!Object} framePayload
-     */
-    _frameNavigated(framePayload) {
-        var frame = this._frames.get(framePayload.id);
-        if (!frame) {
-            // Simulate missed "frameAttached" for a main frame navigation to the new backend process.
-            console.assert(!framePayload.parentId, 'Main frame shouldn\'t have parent frame id.');
-            frame = this._mainFrame;
-        }
-        this._navigateFrame(frame, framePayload.id, framePayload);
-    }
-
-    /**
-     * @param {string} frameId
-     */
-    _frameDetached(frameId) {
-        var frame = this._frames.get(frameId);
-        if (frame)
-            this._removeFramesRecursively(frame);
-    }
-
-    /**
-     * @param {!Frame} frame
-     * @param {string} newFrameId
-     * @param {?Object} newFramePayload
-     */
-    _navigateFrame(frame, newFrameId, newFramePayload) {
-        // Detach all child frames first.
-        for (var child of frame.childFrames())
-            this._removeFramesRecursively(child);
-        this._frames.delete(frame._id, frame);
-        frame._id = newFrameId;
-        frame._adoptPayload(newFramePayload);
-        this._frames.set(newFrameId, frame);
-        this.emit(FrameManager.Events.FrameNavigated, frame);
-    }
-
-    /**
-     * @param {?Frame} parentFrame
-     * @param {!Object} frameTreePayload
-     * @return {!Frame}
-     */
-    _addFramesRecursively(parentFrame, frameTreePayload) {
-        var framePayload = frameTreePayload.frame;
-        var frame = new Frame(parentFrame, framePayload.id, framePayload);
-        this._frames.set(frame._id, frame);
-
-        for (var i = 0; frameTreePayload.childFrames && i < frameTreePayload.childFrames.length; ++i)
-            this._addFramesRecursively(frame, frameTreePayload.childFrames[i]);
-        return frame;
-    }
-
-    /**
-     * @param {!Frame} frame
-     */
-    _removeFramesRecursively(frame) {
-        for (var child of frame.childFrames())
-            this._removeFramesRecursively(child);
-        frame._detach();
-        this._frames.delete(frame._id);
-        this.emit(FrameManager.Events.FrameDetached, frame);
-    }
+  /**
+   * @param {!Frame} frame
+   */
+  _removeFramesRecursively(frame) {
+    for (var child of frame.childFrames())
+      this._removeFramesRecursively(child);
+    frame._detach();
+    this._frames.delete(frame._id);
+    this.emit(FrameManager.Events.FrameDetached, frame);
+  }
 }
 
 /** @enum {string} */
 FrameManager.Events = {
-    FrameAttached: 'frameattached',
-    FrameNavigated: 'framenavigated',
-    FrameDetached: 'framedetached'
+  FrameAttached: 'frameattached',
+  FrameNavigated: 'framenavigated',
+  FrameDetached: 'framedetached'
 };
 
 /**
  * @unrestricted
  */
 class Frame {
-    /**
-    * @param {?Frame} parentFrame
-    * @param {string} frameId
-    * @param {?Object} payload
-    */
-    constructor(parentFrame, frameId, payload) {
-        this._parentFrame = parentFrame;
-        this._url = '';
-        this._id = frameId;
-        this._adoptPayload(payload);
+  /**
+   * @param {?Frame} parentFrame
+   * @param {string} frameId
+   * @param {?Object} payload
+   */
+  constructor(parentFrame, frameId, payload) {
+    this._parentFrame = parentFrame;
+    this._url = '';
+    this._id = frameId;
+    this._adoptPayload(payload);
 
-        /** @type {!Set<!Frame>} */
-        this._childFrames = new Set();
-        if (this._parentFrame)
-            this._parentFrame._childFrames.add(this);
-    }
+    /** @type {!Set<!Frame>} */
+    this._childFrames = new Set();
+    if (this._parentFrame)
+      this._parentFrame._childFrames.add(this);
+  }
 
-    /**
-    * @return {string}
-    */
-    name() {
-        return this._name || '';
-    }
+  /**
+   * @return {string}
+   */
+  name() {
+    return this._name || '';
+  }
 
-    /**
-    * @return {string}
-    */
-    url() {
-        return this._url;
-    }
+  /**
+   * @return {string}
+   */
+  url() {
+    return this._url;
+  }
 
-    /**
-    * @return {string}
-    */
-    securityOrigin() {
-        return this._securityOrigin;
-    }
+  /**
+   * @return {string}
+   */
+  securityOrigin() {
+    return this._securityOrigin;
+  }
 
-    /**
-    * @return {?Frame}
-    */
-    parentFrame() {
-        return this._parentFrame;
-    }
+  /**
+   * @return {?Frame}
+   */
+  parentFrame() {
+    return this._parentFrame;
+  }
 
-    /**
-    * @return {!Array.<!Frame>}
-    */
-    childFrames() {
-        return Array.from(this._childFrames);
-    }
+  /**
+   * @return {!Array.<!Frame>}
+   */
+  childFrames() {
+    return Array.from(this._childFrames);
+  }
 
-    /**
-    * @return {boolean}
-    */
-    isMainFrame() {
-        return !this._detached && !this._parentFrame;
-    }
+  /**
+   * @return {boolean}
+   */
+  isMainFrame() {
+    return !this._detached && !this._parentFrame;
+  }
 
-    /**
-    * @return {boolean}
-    */
-    isDetached() {
-        return this._detached;
-    }
+  /**
+   * @return {boolean}
+   */
+  isDetached() {
+    return this._detached;
+  }
 
-    /**
-    * @param {?Object} framePayload
-    */
-    _adoptPayload(framePayload) {
-        framePayload = framePayload || {
-            name: '',
-            url: '',
-            securityOrigin: '',
-            mimeType: ''
-        };
-        this._name = framePayload.name;
-        this._url = framePayload.url;
-        this._securityOrigin = framePayload.securityOrigin;
-        this._mimeType = framePayload.mimeType;
-    }
+  /**
+   * @param {?Object} framePayload
+   */
+  _adoptPayload(framePayload) {
+    framePayload = framePayload || {
+      name: '',
+      url: '',
+      securityOrigin: '',
+      mimeType: ''
+    };
+    this._name = framePayload.name;
+    this._url = framePayload.url;
+    this._securityOrigin = framePayload.securityOrigin;
+    this._mimeType = framePayload.mimeType;
+  }
 
-    _detach() {
-        this._detached = true;
-        if (this._parentFrame)
-            this._parentFrame._childFrames.delete(this);
-        this._parentFrame = null;
-    }
+  _detach() {
+    this._detached = true;
+    if (this._parentFrame)
+      this._parentFrame._childFrames.delete(this);
+    this._parentFrame = null;
+  }
 }
 
 module.exports = FrameManager;
diff --git a/lib/Page.js b/lib/Page.js
index c3763aee907..b2d04be835d 100644
--- a/lib/Page.js
+++ b/lib/Page.js
@@ -23,548 +23,548 @@ var Dialog = require('./Dialog');
 var FrameManager = require('./FrameManager');
 
 class Page extends EventEmitter {
-    /**
-     * @param {!Connection} client
-     * @return {!Promise<!Page>}
-     */
-    static async create(client) {
-        await Promise.all([
-            client.send('Network.enable', {}),
-            client.send('Page.enable', {}),
-            client.send('Runtime.enable', {}),
-            client.send('Security.enable', {}),
-        ]);
-        var expression = helpers.evaluationString(() => window.devicePixelRatio, []);
-        var {result:{value: screenDPI}} = await client.send('Runtime.evaluate', { expression, returnByValue: true });
-        var frameManager = await FrameManager.create(client);
-        var page = new Page(client, frameManager, screenDPI);
-        // Initialize default page size.
-        await page.setViewportSize({width: 400, height: 300});
-        return page;
-    }
+  /**
+   * @param {!Connection} client
+   * @return {!Promise<!Page>}
+   */
+  static async create(client) {
+    await Promise.all([
+      client.send('Network.enable', {}),
+      client.send('Page.enable', {}),
+      client.send('Runtime.enable', {}),
+      client.send('Security.enable', {}),
+    ]);
+    var expression = helpers.evaluationString(() => window.devicePixelRatio, []);
+    var {result:{value: screenDPI}} = await client.send('Runtime.evaluate', { expression, returnByValue: true });
+    var frameManager = await FrameManager.create(client);
+    var page = new Page(client, frameManager, screenDPI);
+    // Initialize default page size.
+    await page.setViewportSize({width: 400, height: 300});
+    return page;
+  }
 
-    /**
-     * @param {!Connection} client
-     * @param {!FrameManager} frameManager
-     * @param {number} screenDPI
-     */
-    constructor(client, frameManager, screenDPI) {
-        super();
-        this._client = client;
-        this._frameManager = frameManager;
-        this._screenDPI = screenDPI;
-        this._extraHeaders = {};
-        /** @type {!Map<string, function>} */
-        this._inPageCallbacks = new Map();
-        /** @type {?function(!Request)} */
-        this._requestInterceptor = null;
+  /**
+   * @param {!Connection} client
+   * @param {!FrameManager} frameManager
+   * @param {number} screenDPI
+   */
+  constructor(client, frameManager, screenDPI) {
+    super();
+    this._client = client;
+    this._frameManager = frameManager;
+    this._screenDPI = screenDPI;
+    this._extraHeaders = {};
+    /** @type {!Map<string, function>} */
+    this._inPageCallbacks = new Map();
+    /** @type {?function(!Request)} */
+    this._requestInterceptor = null;
 
-        this._screenshotTaskChain = Promise.resolve();
+    this._screenshotTaskChain = Promise.resolve();
 
-        this._frameManager.on(FrameManager.Events.FrameAttached, event => this.emit(Page.Events.FrameAttached, event));
-        this._frameManager.on(FrameManager.Events.FrameDetached, event => this.emit(Page.Events.FrameDetached, event));
-        this._frameManager.on(FrameManager.Events.FrameNavigated, event => this.emit(Page.Events.FrameNavigated, event));
+    this._frameManager.on(FrameManager.Events.FrameAttached, event => this.emit(Page.Events.FrameAttached, event));
+    this._frameManager.on(FrameManager.Events.FrameDetached, event => this.emit(Page.Events.FrameDetached, event));
+    this._frameManager.on(FrameManager.Events.FrameNavigated, event => this.emit(Page.Events.FrameNavigated, event));
 
-        client.on('Network.responseReceived', event => this.emit(Page.Events.ResponseReceived, event.response));
-        client.on('Network.loadingFailed', event => this.emit(Page.Events.ResourceLoadingFailed, event));
-        client.on('Network.requestIntercepted', event => this._onRequestIntercepted(event));
-        client.on('Runtime.consoleAPICalled', event => this._onConsoleAPI(event));
-        client.on('Page.javascriptDialogOpening', event => this._onDialog(event));
-        client.on('Runtime.exceptionThrown', exception => this._handleException(exception.exceptionDetails));
-    }
+    client.on('Network.responseReceived', event => this.emit(Page.Events.ResponseReceived, event.response));
+    client.on('Network.loadingFailed', event => this.emit(Page.Events.ResourceLoadingFailed, event));
+    client.on('Network.requestIntercepted', event => this._onRequestIntercepted(event));
+    client.on('Runtime.consoleAPICalled', event => this._onConsoleAPI(event));
+    client.on('Page.javascriptDialogOpening', event => this._onDialog(event));
+    client.on('Runtime.exceptionThrown', exception => this._handleException(exception.exceptionDetails));
+  }
 
-    /**
-     * @return {!Frame}
-     */
-    mainFrame() {
-        return this._frameManager.mainFrame();
-    }
+  /**
+   * @return {!Frame}
+   */
+  mainFrame() {
+    return this._frameManager.mainFrame();
+  }
 
-    /**
-     * @return {!Array<!Frame>}
-     */
-    frames() {
-        return this._frameManager.frames();
-    }
+  /**
+   * @return {!Array<!Frame>}
+   */
+  frames() {
+    return this._frameManager.frames();
+  }
 
-    /**
-     * @param {?function(!Request)} interceptor
-     */
-    async setRequestInterceptor(interceptor) {
-        this._requestInterceptor = interceptor;
-        await this._client.send('Network.enableRequestInterception', {enabled: !!interceptor});
-    }
+  /**
+   * @param {?function(!Request)} interceptor
+   */
+  async setRequestInterceptor(interceptor) {
+    this._requestInterceptor = interceptor;
+    await this._client.send('Network.enableRequestInterception', {enabled: !!interceptor});
+  }
 
-    /**
-     * @param {!Object} event
-     */
-    _onRequestIntercepted(event) {
-        var request = new Request(this._client, event.InterceptionId, event.request);
-        this._requestInterceptor(request);
-    }
+  /**
+   * @param {!Object} event
+   */
+  _onRequestIntercepted(event) {
+    var request = new Request(this._client, event.InterceptionId, event.request);
+    this._requestInterceptor(request);
+  }
+
+  /**
+   * @param {string} url
+   * @return {!Promise}
+   */
+  async addScriptTag(url) {
+    return this.evaluate(addScriptTag, url);
 
     /**
      * @param {string} url
-     * @return {!Promise}
      */
-    async addScriptTag(url) {
-        return this.evaluate(addScriptTag, url);
+    function addScriptTag(url) {
+      var script = document.createElement('script');
+      script.src = url;
+      var promise = new Promise(x => script.onload = x);
+      document.head.appendChild(script);
+      return promise;
+    }
+  }
 
-        /**
-         * @param {string} url
-         */
-        function addScriptTag(url) {
-            var script = document.createElement('script');
-            script.src = url;
-            var promise = new Promise(x => script.onload = x);
-            document.head.appendChild(script);
-            return promise;
+  /**
+   * @param {string} filePath
+   * @return {!Promise}
+   */
+  async injectFile(filePath) {
+    var expression = fs.readFileSync(filePath, 'utf8');
+    await this._client.send('Runtime.evaluate', { expression, returnByValue: true });
+  }
+
+  /**
+   * @param {string} name
+   * @param {function(?)} callback
+   */
+  async setInPageCallback(name, callback) {
+    if (this._inPageCallbacks[name])
+      throw new Error(`Failed to set in-page callback with name ${name}: window['${name}'] already exists!`);
+    this._inPageCallbacks[name] = callback;
+
+    var expression = helpers.evaluationString(inPageCallback, [name]);
+    await this._client.send('Page.addScriptToEvaluateOnLoad', { scriptSource: expression });
+    await this._client.send('Runtime.evaluate', { expression, returnByValue: true });
+
+    function inPageCallback(callbackName) {
+      window[callbackName] = async(...args) => {
+        const me = window[callbackName];
+        let callbacks = me['callbacks'];
+        if (!callbacks) {
+          callbacks = new Map();
+          me['callbacks'] = callbacks;
         }
+        const seq = (me['lastSeq'] || 0) + 1;
+        me['lastSeq'] = seq;
+        const promise = new Promise(fulfill => callbacks.set(seq, fulfill));
+        // eslint-disable-next-line no-console
+        console.debug('driver:InPageCallback', JSON.stringify({name: callbackName, seq, args}));
+        return promise;
+      };
+    }
+  }
+
+  /**
+   * @param {!Object} headers
+   * @return {!Promise}
+   */
+  async setExtraHTTPHeaders(headers) {
+    this._extraHeaders = {};
+    // Note: header names are case-insensitive.
+    for (var key of Object.keys(headers))
+      this._extraHeaders[key.toLowerCase()] = headers[key];
+    return this._client.send('Network.setExtraHTTPHeaders', { headers });
+  }
+
+  /**
+   * @return {!Object}
+   */
+  extraHTTPHeaders() {
+    return Object.assign({}, this._extraHeaders);
+  }
+
+  /**
+   * @param {string} userAgent
+   * @return {!Promise}
+   */
+  async setUserAgentOverride(userAgent) {
+    this._userAgent = userAgent;
+    return this._client.send('Network.setUserAgentOverride', { userAgent });
+  }
+
+  /**
+   * @return {string}
+   */
+  userAgentOverride() {
+    return this._userAgent;
+  }
+
+  /**
+   * @param {!Object} exceptionDetails
+   */
+  async _handleException(exceptionDetails) {
+    var message = await this._getExceptionMessage(exceptionDetails);
+    this.emit(Page.Events.Error, new Error(message));
+  }
+
+  async _onConsoleAPI(event) {
+    if (event.type === 'debug' && event.args.length && event.args[0].value === 'driver:InPageCallback') {
+      var {name, seq, args} = JSON.parse(event.args[1].value);
+      var result = await this._inPageCallbacks[name](...args);
+      var expression = helpers.evaluationString(deliverResult, [name, seq, result]);
+      this._client.send('Runtime.evaluate', { expression });
+
+      function deliverResult(name, seq, result) {
+        window[name]['callbacks'].get(seq)(result);
+        window[name]['callbacks'].delete(seq);
+      }
+      return;
+    }
+    var values = event.args.map(arg => arg.value || arg.description || '');
+    this.emit(Page.Events.ConsoleMessage, values.join(' '));
+  }
+
+  _onDialog(event) {
+    var dialogType = null;
+    if (event.type === 'alert')
+      dialogType = Dialog.Type.Alert;
+    else if (event.type === 'confirm')
+      dialogType = Dialog.Type.Confirm;
+    else if (event.type === 'prompt')
+      dialogType = Dialog.Type.Prompt;
+    else if (event.type === 'beforeunload')
+      dialogType = Dialog.Type.BeforeUnload;
+    console.assert(dialogType, 'Unknown javascript dialog type: ' + event.type);
+    var dialog = new Dialog(this._client, dialogType, event.message);
+    this.emit(Page.Events.Dialog, dialog);
+  }
+
+  /**
+   * @return {!Promise<string>}
+   */
+  async url() {
+    return this.evaluate(function() {
+      return window.location.href;
+    });
+  }
+
+  /**
+   * @param {string} html
+   * @return {!Promise}
+   */
+  async setContent(html) {
+    var resourceTree = await this._client.send('Page.getResourceTree', {});
+    await this._client.send('Page.setDocumentContent', {
+      frameId: resourceTree.frameTree.frame.id,
+      html: html
+    });
+  }
+
+  /**
+   * @param {string} html
+   * @return {!Promise<boolean>}
+   */
+  async navigate(url) {
+    var loadPromise = new Promise(fulfill => this._client.once('Page.loadEventFired', fulfill)).then(() => true);
+    var interstitialPromise = new Promise(fulfill => this._client.once('Security.certificateError', fulfill)).then(() => false);
+    var referrer = this._extraHeaders.referer;
+    // Await for the command to throw exception in case of illegal arguments.
+    try {
+      await this._client.send('Page.navigate', {url, referrer});
+    } catch (e) {
+      return false;
+    }
+    return await Promise.race([loadPromise, interstitialPromise]);
+  }
+
+  /**
+   * @param {!{width: number, height: number}} size
+   * @return {!Promise}
+   */
+  async setViewportSize(size) {
+    this._size = size;
+    var width = size.width;
+    var height = size.height;
+    var zoom = this._screenDPI;
+    return Promise.all([
+      this._client.send('Emulation.setDeviceMetricsOverride', {
+        width,
+        height,
+        deviceScaleFactor: 1,
+        scale: 1 / zoom,
+        mobile: false,
+        fitWindow: false
+      }),
+      this._client.send('Emulation.setVisibleSize', {
+        width: width / zoom,
+        height: height / zoom,
+      })
+    ]);
+  }
+
+  /**
+   * @return {!{width: number, height: number}}
+   */
+  viewportSize() {
+    return this._size;
+  }
+
+  /**
+   * @param {function()} fun
+   * @param {!Array<*>} args
+   * @return {!Promise<(!Object|undefined)>}
+   */
+  async evaluate(fun, ...args) {
+    var code = helpers.evaluationString(fun, args, false /* wrapInPromise */);
+    var response = await this._client.send('Runtime.evaluate', {
+      expression: code
+    });
+    if (response.exceptionDetails) {
+      var message = await this._getExceptionMessage(response.exceptionDetails);
+      throw new Error('Evaluation failed: ' + message);
     }
 
-    /**
-     * @param {string} filePath
-     * @return {!Promise}
-     */
-    async injectFile(filePath) {
-        var expression = fs.readFileSync(filePath, 'utf8');
-        await this._client.send('Runtime.evaluate', { expression, returnByValue: true });
+    var remoteObject = response.result;
+    if (remoteObject.type !== 'object')
+      return remoteObject.value;
+    var isPromise = remoteObject.type === 'object' && remoteObject.subtype === 'promise';
+    var response = await this._client.send('Runtime.callFunctionOn', {
+      objectId: remoteObject.objectId,
+      functionDeclaration: 'function() { return this; }',
+      returnByValue: true,
+      awaitPromise: isPromise
+    });
+    await this._client.send('Runtime.releaseObject', {
+      objectId: remoteObject.objectId
+    });
+    if (response.exceptionDetails) {
+      var message = await this._getExceptionMessage(response.exceptionDetails);
+      throw new Error('Evaluation failed with ' + message);
     }
 
-    /**
-     * @param {string} name
-     * @param {function(?)} callback
-     */
-    async setInPageCallback(name, callback) {
-        if (this._inPageCallbacks[name])
-            throw new Error(`Failed to set in-page callback with name ${name}: window['${name}'] already exists!`);
-        this._inPageCallbacks[name] = callback;
+    return response.result.value;
+  }
 
-        var expression = helpers.evaluationString(inPageCallback, [name]);
-        await this._client.send('Page.addScriptToEvaluateOnLoad', { scriptSource: expression });
-        await this._client.send('Runtime.evaluate', { expression, returnByValue: true });
+  /**
+   * @param {!Object} exceptionDetails
+   * @return {string}
+   */
+  async _getExceptionMessage(exceptionDetails) {
+    var message = '';
+    var exception = exceptionDetails.exception;
+    if (exception) {
+      var response = await this._client.send('Runtime.callFunctionOn', {
+        objectId: exception.objectId,
+        functionDeclaration: 'function() { return this.message; }',
+        returnByValue: true,
+      });
+      message = response.result.value;
+    } else {
+      message = exceptionDetails.text;
+    }
+    if (exceptionDetails.stackTrace) {
+      for (var callframe of exceptionDetails.stackTrace.callFrames) {
+        var location = callframe.url + ':' + callframe.lineNumber + ':' + callframe.columnNumber;
+        var functionName = callframe.functionName || '<anonymous>';
+        message += `\n    at ${functionName} (${location})`;
+      }
+    }
+    return message;
+  }
 
-        function inPageCallback(callbackName) {
-            window[callbackName] = async(...args) => {
-                const me = window[callbackName];
-                let callbacks = me['callbacks'];
-                if (!callbacks) {
-                    callbacks = new Map();
-                    me['callbacks'] = callbacks;
-                }
-                const seq = (me['lastSeq'] || 0) + 1;
-                me['lastSeq'] = seq;
-                const promise = new Promise(fulfill => callbacks.set(seq, fulfill));
-                // eslint-disable-next-line no-console
-                console.debug('driver:InPageCallback', JSON.stringify({name: callbackName, seq, args}));
-                return promise;
-            };
-        }
+  /**
+   * @param {function()} fun
+   * @param {!Array<*>} args
+   * @return {!Promise}
+   */
+  async evaluateOnInitialized(fun, ...args) {
+    var code = helpers.evaluationString(fun, args, false /* wrapInPromise */);
+    await this._client.send('Page.addScriptToEvaluateOnLoad', {
+      scriptSource: code
+    });
+  }
+
+  /**
+   * @param {!Object=} options
+   * @return {!Promise<!Buffer>}
+   */
+  async screenshot(options) {
+    options = options || {};
+    var screenshotType = null;
+    if (options.path) {
+      var mimeType = mime.lookup(options.path);
+      if (mimeType === 'image/png')
+        screenshotType = 'png';
+      else if (mimeType === 'image/jpeg')
+        screenshotType = 'jpeg';
+      console.assert(screenshotType, 'Unsupported screenshot mime type: ' + mimeType);
+    }
+    if (options.type) {
+      console.assert(!screenshotType || options.type === screenshotType, `Passed screenshot type '${options.type}' does not match the type inferred from the file path: '${screenshotType}'`);
+      console.assert(options.type === 'png' || options.type === 'jpeg', 'Unknown options.type value: ' + options.type);
+      screenshotType = options.type;
+    }
+    if (!screenshotType)
+      screenshotType = 'png';
+
+    if (options.quality) {
+      console.assert(screenshotType === 'jpeg', 'options.quality is unsupported for the ' + screenshotType + ' screenshots');
+      console.assert(typeof options.quality === 'number', 'Expected options.quality to be a number but found ' + (typeof options.quality));
+      console.assert(Number.isInteger(options.quality), 'Expected options.quality to be an integer');
+      console.assert(options.quality >= 0 && options.quality <= 100, 'Expected options.quality to be between 0 and 100 (inclusive), got ' + options.quality);
+    }
+    console.assert(!options.clip || !options.fullPage, 'options.clip and options.fullPage are exclusive');
+    if (options.clip) {
+      console.assert(typeof options.clip.x === 'number', 'Expected options.clip.x to be a number but found ' + (typeof options.clip.x));
+      console.assert(typeof options.clip.y === 'number', 'Expected options.clip.y to be a number but found ' + (typeof options.clip.y));
+      console.assert(typeof options.clip.width === 'number', 'Expected options.clip.width to be a number but found ' + (typeof options.clip.width));
+      console.assert(typeof options.clip.height === 'number', 'Expected options.clip.height to be a number but found ' + (typeof options.clip.height));
+    }
+    this._screenshotTaskChain = this._screenshotTaskChain.then(this._screenshotTask.bind(this, screenshotType, options));
+    return this._screenshotTaskChain;
+  }
+
+  /**
+   * @param {string} screenshotType
+   * @param {!Object=} options
+   * @return {!Promise<!Buffer>}
+   */
+  async _screenshotTask(screenshotType, options) {
+    if (options.clip) {
+      await Promise.all([
+        this._client.send('Emulation.setVisibleSize', {
+          width: Math.ceil(options.clip.width / this._screenDPI),
+          height: Math.ceil(options.clip.height / this._screenDPI),
+        }),
+        this._client.send('Emulation.forceViewport', {
+          x: options.clip.x / this._screenDPI,
+          y: options.clip.y / this._screenDPI,
+          scale: 1,
+        })
+      ]);
+    } else if (options.fullPage) {
+      var response = await this._client.send('Page.getLayoutMetrics');
+      await Promise.all([
+        this._client.send('Emulation.setVisibleSize', {
+          width: Math.ceil(response.contentSize.width / this._screenDPI),
+          height: Math.ceil(response.contentSize.height / this._screenDPI),
+        }),
+        this._client.send('Emulation.forceViewport', {
+          x: 0,
+          y: 0,
+          scale: 1,
+        })
+      ]);
+    }
+    var result = await this._client.send('Page.captureScreenshot', {
+      fromSurface: true,
+      format: screenshotType,
+      quality: options.quality
+    });
+    if (options.clip || options.fullPage) {
+      await Promise.all([
+        this.setViewportSize(this.viewportSize()),
+        this._client.send('Emulation.resetViewport')
+      ]);
+    }
+    var buffer = new Buffer(result.data, 'base64');
+    if (options.path)
+      fs.writeFileSync(options.path, buffer);
+    return buffer;
+  }
+
+  /**
+   * @param {string} filePath
+   * @param {!Object=} options
+   * @return {!Promise}
+   */
+  async printToPDF(filePath, options) {
+    options = options || {};
+
+    var scale = options.scale || 1;
+    var displayHeaderFooter = options.displayHeaderFooter || false;
+    var printBackground = options.printBackground || true;
+    var landscape = options.landscape || false;
+    var pageRanges = options.pageRanges || '';
+
+    var paperWidth = 8.5;
+    var paperHeight = 11;
+    if (options.format) {
+      var format = Page.PaperFormats[options.format];
+      console.assert(format, 'Unknown paper format: ' + options.format);
+      paperWidth = format.width;
+      paperHeight = format.height;
+    } else {
+      paperWidth = convertPrintParameterToInches(options.width) || paperWidth;
+      paperHeight = convertPrintParameterToInches(options.height) || paperHeight;
     }
 
-    /**
-     * @param {!Object} headers
-     * @return {!Promise}
-     */
-    async setExtraHTTPHeaders(headers) {
-        this._extraHeaders = {};
-        // Note: header names are case-insensitive.
-        for (var key of Object.keys(headers))
-            this._extraHeaders[key.toLowerCase()] = headers[key];
-        return this._client.send('Network.setExtraHTTPHeaders', { headers });
-    }
+    var marginOptions = options.margin || {};
+    var marginTop = convertPrintParameterToInches(marginOptions.top) || 0;
+    var marginLeft = convertPrintParameterToInches(marginOptions.left) || 0;
+    var marginBottom = convertPrintParameterToInches(marginOptions.bottom) || 0;
+    var marginRight = convertPrintParameterToInches(marginOptions.right) || 0;
 
-    /**
-     * @return {!Object}
-     */
-    extraHTTPHeaders() {
-        return Object.assign({}, this._extraHeaders);
-    }
+    var result = await this._client.send('Page.printToPDF', {
+      landscape: landscape,
+      displayHeaderFooter: displayHeaderFooter,
+      printBackground: printBackground,
+      scale: scale,
+      paperWidth: paperWidth,
+      paperHeight: paperHeight,
+      marginTop: marginTop,
+      marginBottom: marginBottom,
+      marginLeft: marginLeft,
+      marginRight: marginRight,
+      pageRanges: pageRanges
+    });
+    var buffer = new Buffer(result.data, 'base64');
+    fs.writeFileSync(filePath, buffer);
+  }
 
-    /**
-     * @param {string} userAgent
-     * @return {!Promise}
-     */
-    async setUserAgentOverride(userAgent) {
-        this._userAgent = userAgent;
-        return this._client.send('Network.setUserAgentOverride', { userAgent });
-    }
+  /**
+   * @return {!Promise<string>}
+   */
+  async plainText() {
+    return this.evaluate(function() {
+      return document.body.innerText;
+    });
+  }
 
-    /**
-     * @return {string}
-     */
-    userAgentOverride() {
-        return this._userAgent;
-    }
+  /**
+   * @return {!Promise<string>}
+   */
+  async title() {
+    return this.evaluate(function() {
+      return document.title;
+    });
+  }
 
-    /**
-     * @param {!Object} exceptionDetails
-     */
-    async _handleException(exceptionDetails) {
-        var message = await this._getExceptionMessage(exceptionDetails);
-        this.emit(Page.Events.Error, new Error(message));
-    }
-
-    async _onConsoleAPI(event) {
-        if (event.type === 'debug' && event.args.length && event.args[0].value === 'driver:InPageCallback') {
-            var {name, seq, args} = JSON.parse(event.args[1].value);
-            var result = await this._inPageCallbacks[name](...args);
-            var expression = helpers.evaluationString(deliverResult, [name, seq, result]);
-            this._client.send('Runtime.evaluate', { expression });
-
-            function deliverResult(name, seq, result) {
-                window[name]['callbacks'].get(seq)(result);
-                window[name]['callbacks'].delete(seq);
-            }
-            return;
-        }
-        var values = event.args.map(arg => arg.value || arg.description || '');
-        this.emit(Page.Events.ConsoleMessage, values.join(' '));
-    }
-
-    _onDialog(event) {
-        var dialogType = null;
-        if (event.type === 'alert')
-            dialogType = Dialog.Type.Alert;
-        else if (event.type === 'confirm')
-            dialogType = Dialog.Type.Confirm;
-        else if (event.type === 'prompt')
-            dialogType = Dialog.Type.Prompt;
-        else if (event.type === 'beforeunload')
-            dialogType = Dialog.Type.BeforeUnload;
-        console.assert(dialogType, 'Unknown javascript dialog type: ' + event.type);
-        var dialog = new Dialog(this._client, dialogType, event.message);
-        this.emit(Page.Events.Dialog, dialog);
-    }
-
-    /**
-     * @return {!Promise<string>}
-     */
-    async url() {
-        return this.evaluate(function() {
-            return window.location.href;
-        });
-    }
-
-    /**
-     * @param {string} html
-     * @return {!Promise}
-     */
-    async setContent(html) {
-        var resourceTree = await this._client.send('Page.getResourceTree', {});
-        await this._client.send('Page.setDocumentContent', {
-            frameId: resourceTree.frameTree.frame.id,
-            html: html
-        });
-    }
-
-    /**
-     * @param {string} html
-     * @return {!Promise<boolean>}
-     */
-    async navigate(url) {
-        var loadPromise = new Promise(fulfill => this._client.once('Page.loadEventFired', fulfill)).then(() => true);
-        var interstitialPromise = new Promise(fulfill => this._client.once('Security.certificateError', fulfill)).then(() => false);
-        var referrer = this._extraHeaders.referer;
-        // Await for the command to throw exception in case of illegal arguments.
-        try {
-            await this._client.send('Page.navigate', {url, referrer});
-        } catch (e) {
-            return false;
-        }
-        return await Promise.race([loadPromise, interstitialPromise]);
-    }
-
-    /**
-     * @param {!{width: number, height: number}} size
-     * @return {!Promise}
-     */
-    async setViewportSize(size) {
-        this._size = size;
-        var width = size.width;
-        var height = size.height;
-        var zoom = this._screenDPI;
-        return Promise.all([
-            this._client.send('Emulation.setDeviceMetricsOverride', {
-                width,
-                height,
-                deviceScaleFactor: 1,
-                scale: 1 / zoom,
-                mobile: false,
-                fitWindow: false
-            }),
-            this._client.send('Emulation.setVisibleSize', {
-                width: width / zoom,
-                height: height / zoom,
-            })
-        ]);
-    }
-
-    /**
-     * @return {!{width: number, height: number}}
-     */
-    viewportSize() {
-        return this._size;
-    }
-
-    /**
-     * @param {function()} fun
-     * @param {!Array<*>} args
-     * @return {!Promise<(!Object|undefined)>}
-     */
-    async evaluate(fun, ...args) {
-        var code = helpers.evaluationString(fun, args, false /* wrapInPromise */);
-        var response = await this._client.send('Runtime.evaluate', {
-            expression: code
-        });
-        if (response.exceptionDetails) {
-            var message = await this._getExceptionMessage(response.exceptionDetails);
-            throw new Error('Evaluation failed: ' + message);
-        }
-
-        var remoteObject = response.result;
-        if (remoteObject.type !== 'object')
-            return remoteObject.value;
-        var isPromise = remoteObject.type === 'object' && remoteObject.subtype === 'promise';
-        var response = await this._client.send('Runtime.callFunctionOn', {
-            objectId: remoteObject.objectId,
-            functionDeclaration: 'function() { return this; }',
-            returnByValue: true,
-            awaitPromise: isPromise
-        });
-        await this._client.send('Runtime.releaseObject', {
-            objectId: remoteObject.objectId
-        });
-        if (response.exceptionDetails) {
-            var message = await this._getExceptionMessage(response.exceptionDetails);
-            throw new Error('Evaluation failed with ' + message);
-        }
-
-        return response.result.value;
-    }
-
-    /**
-     * @param {!Object} exceptionDetails
-     * @return {string}
-     */
-    async _getExceptionMessage(exceptionDetails) {
-        var message = '';
-        var exception = exceptionDetails.exception;
-        if (exception) {
-            var response = await this._client.send('Runtime.callFunctionOn', {
-                objectId: exception.objectId,
-                functionDeclaration: 'function() { return this.message; }',
-                returnByValue: true,
-            });
-            message = response.result.value;
-        } else {
-            message = exceptionDetails.text;
-        }
-        if (exceptionDetails.stackTrace) {
-            for (var callframe of exceptionDetails.stackTrace.callFrames) {
-                var location = callframe.url + ':' + callframe.lineNumber + ':' + callframe.columnNumber;
-                var functionName = callframe.functionName || '<anonymous>';
-                message += `\n    at ${functionName} (${location})`;
-            }
-        }
-        return message;
-    }
-
-    /**
-     * @param {function()} fun
-     * @param {!Array<*>} args
-     * @return {!Promise}
-     */
-    async evaluateOnInitialized(fun, ...args) {
-        var code = helpers.evaluationString(fun, args, false /* wrapInPromise */);
-        await this._client.send('Page.addScriptToEvaluateOnLoad', {
-            scriptSource: code
-        });
-    }
-
-    /**
-     * @param {!Object=} options
-     * @return {!Promise<!Buffer>}
-     */
-    async screenshot(options) {
-        options = options || {};
-        var screenshotType = null;
-        if (options.path) {
-            var mimeType = mime.lookup(options.path);
-            if (mimeType === 'image/png')
-                screenshotType = 'png';
-            else if (mimeType === 'image/jpeg')
-                screenshotType = 'jpeg';
-            console.assert(screenshotType, 'Unsupported screenshot mime type: ' + mimeType);
-        }
-        if (options.type) {
-            console.assert(!screenshotType || options.type === screenshotType, `Passed screenshot type '${options.type}' does not match the type inferred from the file path: '${screenshotType}'`);
-            console.assert(options.type === 'png' || options.type === 'jpeg', 'Unknown options.type value: ' + options.type);
-            screenshotType = options.type;
-        }
-        if (!screenshotType)
-            screenshotType = 'png';
-
-        if (options.quality) {
-            console.assert(screenshotType === 'jpeg', 'options.quality is unsupported for the ' + screenshotType + ' screenshots');
-            console.assert(typeof options.quality === 'number', 'Expected options.quality to be a number but found ' + (typeof options.quality));
-            console.assert(Number.isInteger(options.quality), 'Expected options.quality to be an integer');
-            console.assert(options.quality >= 0 && options.quality <= 100, 'Expected options.quality to be between 0 and 100 (inclusive), got ' + options.quality);
-        }
-        console.assert(!options.clip || !options.fullPage, 'options.clip and options.fullPage are exclusive');
-        if (options.clip) {
-            console.assert(typeof options.clip.x === 'number', 'Expected options.clip.x to be a number but found ' + (typeof options.clip.x));
-            console.assert(typeof options.clip.y === 'number', 'Expected options.clip.y to be a number but found ' + (typeof options.clip.y));
-            console.assert(typeof options.clip.width === 'number', 'Expected options.clip.width to be a number but found ' + (typeof options.clip.width));
-            console.assert(typeof options.clip.height === 'number', 'Expected options.clip.height to be a number but found ' + (typeof options.clip.height));
-        }
-        this._screenshotTaskChain = this._screenshotTaskChain.then(this._screenshotTask.bind(this, screenshotType, options));
-        return this._screenshotTaskChain;
-    }
-
-    /**
-     * @param {string} screenshotType
-     * @param {!Object=} options
-     * @return {!Promise<!Buffer>}
-     */
-    async _screenshotTask(screenshotType, options) {
-        if (options.clip) {
-            await Promise.all([
-                this._client.send('Emulation.setVisibleSize', {
-                    width: Math.ceil(options.clip.width / this._screenDPI),
-                    height: Math.ceil(options.clip.height / this._screenDPI),
-                }),
-                this._client.send('Emulation.forceViewport', {
-                    x: options.clip.x / this._screenDPI,
-                    y: options.clip.y / this._screenDPI,
-                    scale: 1,
-                })
-            ]);
-        } else if (options.fullPage) {
-            var response = await this._client.send('Page.getLayoutMetrics');
-            await Promise.all([
-                this._client.send('Emulation.setVisibleSize', {
-                    width: Math.ceil(response.contentSize.width / this._screenDPI),
-                    height: Math.ceil(response.contentSize.height / this._screenDPI),
-                }),
-                this._client.send('Emulation.forceViewport', {
-                    x: 0,
-                    y: 0,
-                    scale: 1,
-                })
-            ]);
-        }
-        var result = await this._client.send('Page.captureScreenshot', {
-            fromSurface: true,
-            format: screenshotType,
-            quality: options.quality
-        });
-        if (options.clip || options.fullPage) {
-            await Promise.all([
-                this.setViewportSize(this.viewportSize()),
-                this._client.send('Emulation.resetViewport')
-            ]);
-        }
-        var buffer = new Buffer(result.data, 'base64');
-        if (options.path)
-            fs.writeFileSync(options.path, buffer);
-        return buffer;
-    }
-
-    /**
-     * @param {string} filePath
-     * @param {!Object=} options
-     * @return {!Promise}
-     */
-    async printToPDF(filePath, options) {
-        options = options || {};
-
-        var scale = options.scale || 1;
-        var displayHeaderFooter = options.displayHeaderFooter || false;
-        var printBackground = options.printBackground || true;
-        var landscape = options.landscape || false;
-        var pageRanges = options.pageRanges || '';
-
-        var paperWidth = 8.5;
-        var paperHeight = 11;
-        if (options.format) {
-            var format = Page.PaperFormats[options.format];
-            console.assert(format, 'Unknown paper format: ' + options.format);
-            paperWidth = format.width;
-            paperHeight = format.height;
-        } else {
-            paperWidth = convertPrintParameterToInches(options.width) || paperWidth;
-            paperHeight = convertPrintParameterToInches(options.height) || paperHeight;
-        }
-
-        var marginOptions = options.margin || {};
-        var marginTop = convertPrintParameterToInches(marginOptions.top) || 0;
-        var marginLeft = convertPrintParameterToInches(marginOptions.left) || 0;
-        var marginBottom = convertPrintParameterToInches(marginOptions.bottom) || 0;
-        var marginRight = convertPrintParameterToInches(marginOptions.right) || 0;
-
-        var result = await this._client.send('Page.printToPDF', {
-            landscape: landscape,
-            displayHeaderFooter: displayHeaderFooter,
-            printBackground: printBackground,
-            scale: scale,
-            paperWidth: paperWidth,
-            paperHeight: paperHeight,
-            marginTop: marginTop,
-            marginBottom: marginBottom,
-            marginLeft: marginLeft,
-            marginRight: marginRight,
-            pageRanges: pageRanges
-        });
-        var buffer = new Buffer(result.data, 'base64');
-        fs.writeFileSync(filePath, buffer);
-    }
-
-    /**
-     * @return {!Promise<string>}
-     */
-    async plainText() {
-        return this.evaluate(function() {
-            return document.body.innerText;
-        });
-    }
-
-    /**
-     * @return {!Promise<string>}
-     */
-    async title() {
-        return this.evaluate(function() {
-            return document.title;
-        });
-    }
-
-    /**
-     * @return {!Promise}
-     */
-    async close() {
-        await this._client.dispose();
-    }
+  /**
+   * @return {!Promise}
+   */
+  async close() {
+    await this._client.dispose();
+  }
 }
 
 /** @enum {string} */
 Page.PaperFormats = {
-    Letter: {width: 8.5, height: 11},
-    Legal: {width: 8.5, height: 14},
-    Tabloid: {width: 11, height: 17},
-    Ledger: {width: 17, height: 11},
-    A0: {width: 33.1, height: 46.8 },
-    A1: {width: 23.4, height: 33.1 },
-    A2: {width: 16.5, height: 23.4 },
-    A3: {width: 11.7, height: 16.5 },
-    A4: {width: 8.27, height: 11.7 },
-    A5: {width: 5.83, height: 8.27 },
+  Letter: {width: 8.5, height: 11},
+  Legal: {width: 8.5, height: 14},
+  Tabloid: {width: 11, height: 17},
+  Ledger: {width: 17, height: 11},
+  A0: {width: 33.1, height: 46.8 },
+  A1: {width: 23.4, height: 33.1 },
+  A2: {width: 16.5, height: 23.4 },
+  A3: {width: 11.7, height: 16.5 },
+  A4: {width: 8.27, height: 11.7 },
+  A5: {width: 5.83, height: 8.27 },
 };
 
 var unitToPixels = {
-    'px': 1,
-    'in': 96,
-    'cm': 37.8,
-    'mm': 3.78
+  'px': 1,
+  'in': 96,
+  'cm': 37.8,
+  'mm': 3.78
 };
 
 /**
@@ -572,42 +572,42 @@ var unitToPixels = {
  * @return {(number|undefined)}
  */
 function convertPrintParameterToInches(parameter) {
-    if (typeof parameter === 'undefined')
-        return undefined;
-    var pixels;
-    if (typeof parameter === 'number') {
-        // Treat numbers as pixel values to be aligned with phantom's paperSize.
-        pixels = /** @type {number} */ (parameter);
-    } else if (typeof parameter === 'string') {
-        var text = parameter;
-        var unit = text.substring(text.length - 2).toLowerCase();
-        var valueText = '';
-        if (unitToPixels.hasOwnProperty(unit)) {
-            valueText = text.substring(0, text.length - 2);
-        } else {
-            // In case of unknown unit try to parse the whole parameter as number of pixels.
-            // This is consistent with phantom's paperSize behavior.
-            unit = 'px';
-            valueText = text;
-        }
-        var value = Number(valueText);
-        console.assert(!isNaN(value), 'Failed to parse parameter value: ' + text);
-        pixels = value * unitToPixels[unit];
+  if (typeof parameter === 'undefined')
+    return undefined;
+  var pixels;
+  if (typeof parameter === 'number') {
+    // Treat numbers as pixel values to be aligned with phantom's paperSize.
+    pixels = /** @type {number} */ (parameter);
+  } else if (typeof parameter === 'string') {
+    var text = parameter;
+    var unit = text.substring(text.length - 2).toLowerCase();
+    var valueText = '';
+    if (unitToPixels.hasOwnProperty(unit)) {
+      valueText = text.substring(0, text.length - 2);
     } else {
-        throw new Error('printToPDF Cannot handle parameter type: ' + (typeof parameter));
+      // In case of unknown unit try to parse the whole parameter as number of pixels.
+      // This is consistent with phantom's paperSize behavior.
+      unit = 'px';
+      valueText = text;
     }
-    return pixels / 96;
+    var value = Number(valueText);
+    console.assert(!isNaN(value), 'Failed to parse parameter value: ' + text);
+    pixels = value * unitToPixels[unit];
+  } else {
+    throw new Error('printToPDF Cannot handle parameter type: ' + (typeof parameter));
+  }
+  return pixels / 96;
 }
 
 Page.Events = {
-    ConsoleMessage: 'consolemessage',
-    Dialog: 'dialog',
-    Error: 'error',
-    ResourceLoadingFailed: 'resourceloadingfailed',
-    ResponseReceived: 'responsereceived',
-    FrameAttached: 'frameattached',
-    FrameDetached: 'framedetached',
-    FrameNavigated: 'framenavigated',
+  ConsoleMessage: 'consolemessage',
+  Dialog: 'dialog',
+  Error: 'error',
+  ResourceLoadingFailed: 'resourceloadingfailed',
+  ResponseReceived: 'responsereceived',
+  FrameAttached: 'frameattached',
+  FrameDetached: 'framedetached',
+  FrameNavigated: 'framenavigated',
 };
 
 module.exports = Page;
diff --git a/lib/Request.js b/lib/Request.js
index f8797a9dcba..e74fc828f77 100644
--- a/lib/Request.js
+++ b/lib/Request.js
@@ -15,112 +15,112 @@
  */
 
 class Request {
-    /**
-     * @param {!Connection} client
-     * @param {string} interceptionId
-     * @param {!Object} payload
-     */
-    constructor(client, interceptionId, payload) {
-        this._client = client;
-        this._interceptionId = interceptionId;
-        this._url = payload.url;
-        this._method = payload.method;
-        this._headers = payload.headers;
-        this._postData = payload.postData;
+  /**
+   * @param {!Connection} client
+   * @param {string} interceptionId
+   * @param {!Object} payload
+   */
+  constructor(client, interceptionId, payload) {
+    this._client = client;
+    this._interceptionId = interceptionId;
+    this._url = payload.url;
+    this._method = payload.method;
+    this._headers = payload.headers;
+    this._postData = payload.postData;
 
-        this._urlOverride = undefined;
-        this._methodOverride = undefined;
-        this._postDataOverride = undefined;
+    this._urlOverride = undefined;
+    this._methodOverride = undefined;
+    this._postDataOverride = undefined;
 
-        this._handled = false;
-    }
+    this._handled = false;
+  }
 
-    /**
-     * @return {string}
-     */
-    url() {
-        return this._urlOverride || this._url;
-    }
+  /**
+   * @return {string}
+   */
+  url() {
+    return this._urlOverride || this._url;
+  }
 
-    /**
-     * @param {string} url
-     */
-    setUrl(url) {
-        this._urlOverride = url;
-    }
+  /**
+   * @param {string} url
+   */
+  setUrl(url) {
+    this._urlOverride = url;
+  }
 
-    /**
-     * @return {string}
-     */
-    method() {
-        return this._methodOverride || this._method;
-    }
+  /**
+   * @return {string}
+   */
+  method() {
+    return this._methodOverride || this._method;
+  }
 
-    /**
-     * @param {string} method
-     */
-    setMethod(method) {
-        this._methodOverride = method;
-    }
+  /**
+   * @param {string} method
+   */
+  setMethod(method) {
+    this._methodOverride = method;
+  }
 
-    /**
-     * @return {!Object}
-     */
-    headers() {
-        return Object.assign({}, this._headersOverride || this._headers);
-    }
+  /**
+   * @return {!Object}
+   */
+  headers() {
+    return Object.assign({}, this._headersOverride || this._headers);
+  }
 
-    /**
-     * @param {string} key
-     * @param {string} value
-     */
-    setHeader(key, value) {
-        if (!this._headersOverride)
-            this._headersOverride = Object.assign({}, this._headers);
-        this._headersOverride[key] = value;
-    }
+  /**
+   * @param {string} key
+   * @param {string} value
+   */
+  setHeader(key, value) {
+    if (!this._headersOverride)
+      this._headersOverride = Object.assign({}, this._headers);
+    this._headersOverride[key] = value;
+  }
 
-    /**
-     * @return {(string|undefined)}
-     */
-    postData() {
-        return this._postDataOverride || this._postData;
-    }
+  /**
+   * @return {(string|undefined)}
+   */
+  postData() {
+    return this._postDataOverride || this._postData;
+  }
 
-    /**
-     * @return {(string|undefined)}
-     */
-    setPostData(data) {
-        this._postDataOverride = data;
-    }
+  /**
+   * @return {(string|undefined)}
+   */
+  setPostData(data) {
+    this._postDataOverride = data;
+  }
 
-    abort() {
-        console.assert(!this._handled, 'This request is already handled!');
-        this._handled = true;
-        this._client.send('Network.continueInterceptedRequest', {
-            interceptionId: this._interceptionId,
-            errorReason: 'Aborted'
-        });
-    }
+  abort() {
+    console.assert(!this._handled, 'This request is already handled!');
+    this._handled = true;
+    this._client.send('Network.continueInterceptedRequest', {
+      interceptionId: this._interceptionId,
+      errorReason: 'Aborted'
+    });
+  }
 
-    continue() {
-        console.assert(!this._handled, 'This request is already handled!');
-        this._handled = true;
-        this._client.send('Network.continueInterceptedRequest', {
-            interceptionId: this._interceptionId,
-            url: this._urlOverride,
-            method: this._methodOverride,
-            postData: this._postDataOverride,
-            headers: this._headersOverride
-        });
-    }
+  continue() {
+    console.assert(!this._handled, 'This request is already handled!');
+    this._handled = true;
+    this._client.send('Network.continueInterceptedRequest', {
+      interceptionId: this._interceptionId,
+      url: this._urlOverride,
+      method: this._methodOverride,
+      postData: this._postDataOverride,
+      headers: this._headersOverride
+    });
+  }
 
-    /**
-     * @return {boolean}
-     */
-    handled() {
-        return this._handled;
-    }
+  /**
+   * @return {boolean}
+   */
+  handled() {
+    return this._handled;
+  }
 }
 
 module.exports = Request;
diff --git a/lib/helpers.js b/lib/helpers.js
index af0ab1c78b2..d6af1ad0f67 100644
--- a/lib/helpers.js
+++ b/lib/helpers.js
@@ -15,21 +15,20 @@
  */
 
 module.exports = {
-
-    /**
-     * @param {function()} fun
-     * @param {!Array<*>} args
-     * @param {boolean=} wrapInPromise
-     * @param {string=} sourceURL
-     * @return {string}
-     */
-    evaluationString: function(fun, args, wrapInPromise, sourceURL) {
-        var argsString = args.map(x => JSON.stringify(x)).join(',');
-        var code = `(${fun.toString()})(${argsString})`;
-        if (wrapInPromise)
-            code = `Promise.resolve(${code})`;
-        if (sourceURL)
-            code += `\n//# sourceURL=${sourceURL}`;
-        return code;
-    }
+  /**
+   * @param {function()} fun
+   * @param {!Array<*>} args
+   * @param {boolean=} wrapInPromise
+   * @param {string=} sourceURL
+   * @return {string}
+   */
+  evaluationString: function(fun, args, wrapInPromise, sourceURL) {
+    var argsString = args.map(x => JSON.stringify(x)).join(',');
+    var code = `(${fun.toString()})(${argsString})`;
+    if (wrapInPromise)
+      code = `Promise.resolve(${code})`;
+    if (sourceURL)
+      code += `\n//# sourceURL=${sourceURL}`;
+    return code;
+  }
 };
diff --git a/package-lock.json b/package-lock.json
index ebdaf885b93..4306d1f20be 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -3,6 +3,86 @@
   "version": "0.0.1",
   "lockfileVersion": 1,
   "dependencies": {
+    "acorn": {
+      "version": "5.0.3",
+      "resolved": "https://registry.npmjs.org/acorn/-/acorn-5.0.3.tgz",
+      "integrity": "sha1-xGDfCEkUY/AozLguqzcwvwEIez0=",
+      "dev": true
+    },
+    "acorn-jsx": {
+      "version": "3.0.1",
+      "resolved": "https://registry.npmjs.org/acorn-jsx/-/acorn-jsx-3.0.1.tgz",
+      "integrity": "sha1-r9+UiPsezvyDSPb7IvRk4ypYs2s=",
+      "dev": true,
+      "dependencies": {
+        "acorn": {
+          "version": "3.3.0",
+          "resolved": "https://registry.npmjs.org/acorn/-/acorn-3.3.0.tgz",
+          "integrity": "sha1-ReN/s56No/JbruP/U2niu18iAXo=",
+          "dev": true
+        }
+      }
+    },
+    "ajv": {
+      "version": "4.11.8",
+      "resolved": "https://registry.npmjs.org/ajv/-/ajv-4.11.8.tgz",
+      "integrity": "sha1-gv+wKynmYq5TvcIK8VlHcGc5xTY=",
+      "dev": true
+    },
+    "ajv-keywords": {
+      "version": "1.5.1",
+      "resolved": "https://registry.npmjs.org/ajv-keywords/-/ajv-keywords-1.5.1.tgz",
+      "integrity": "sha1-MU3QpLM2j609/NxU7eYXG4htrzw=",
+      "dev": true
+    },
+    "ansi-escapes": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/ansi-escapes/-/ansi-escapes-2.0.0.tgz",
+      "integrity": "sha1-W65SvkJIeN2Xg+iRDj/Cki6DyBs=",
+      "dev": true
+    },
+    "ansi-regex": {
+      "version": "2.1.1",
+      "resolved": "https://registry.npmjs.org/ansi-regex/-/ansi-regex-2.1.1.tgz",
+      "integrity": "sha1-w7M6te42DYbg5ijwRorn7yfWVN8=",
+      "dev": true
+    },
+    "ansi-styles": {
+      "version": "2.2.1",
+      "resolved": "https://registry.npmjs.org/ansi-styles/-/ansi-styles-2.2.1.tgz",
+      "integrity": "sha1-tDLdM1i2NM914eRmQ2gkBTPB3b4=",
+      "dev": true
+    },
+    "argparse": {
+      "version": "1.0.9",
+      "resolved": "https://registry.npmjs.org/argparse/-/argparse-1.0.9.tgz",
+      "integrity": "sha1-c9g7wmP4bpf4zE9rrhsOkKfSLIY=",
+      "dev": true
+    },
+    "array-union": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/array-union/-/array-union-1.0.2.tgz",
+      "integrity": "sha1-mjRBDk9OPaI96jdb5b5w8kd47Dk=",
+      "dev": true
+    },
+    "array-uniq": {
+      "version": "1.0.3",
+      "resolved": "https://registry.npmjs.org/array-uniq/-/array-uniq-1.0.3.tgz",
+      "integrity": "sha1-r2rId6Jcx/dOBYiUdThY39sk/bY=",
+      "dev": true
+    },
+    "arrify": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/arrify/-/arrify-1.0.1.tgz",
+      "integrity": "sha1-iYUI2iIm84DfkEcoRWhJwVAaSw0=",
+      "dev": true
+    },
+    "babel-code-frame": {
+      "version": "6.22.0",
+      "resolved": "https://registry.npmjs.org/babel-code-frame/-/babel-code-frame-6.22.0.tgz",
+      "integrity": "sha1-AnYgvuVnqIwyVhV05/0IAdMxGOQ=",
+      "dev": true
+    },
     "balanced-match": {
       "version": "https://registry.npmjs.org/balanced-match/-/balanced-match-0.4.2.tgz",
       "integrity": "sha1-yz8+PHMtwPAe5wtAPzAuYddwmDg="
@@ -16,6 +96,48 @@
       "version": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.7.tgz",
       "integrity": "sha1-Pv/DxQ4ABTH7cg6v+A8K6O8jz1k="
     },
+    "caller-path": {
+      "version": "0.1.0",
+      "resolved": "https://registry.npmjs.org/caller-path/-/caller-path-0.1.0.tgz",
+      "integrity": "sha1-lAhe9jWB7NPaqSREqP6U6CV3dR8=",
+      "dev": true
+    },
+    "callsites": {
+      "version": "0.2.0",
+      "resolved": "https://registry.npmjs.org/callsites/-/callsites-0.2.0.tgz",
+      "integrity": "sha1-r6uWJikQp/M8GaV3WCXGnzTjUMo=",
+      "dev": true
+    },
+    "chalk": {
+      "version": "1.1.3",
+      "resolved": "https://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
+      "integrity": "sha1-qBFcVeSnAv5NFQq9OHKCKn4J/Jg=",
+      "dev": true
+    },
+    "circular-json": {
+      "version": "0.3.1",
+      "resolved": "https://registry.npmjs.org/circular-json/-/circular-json-0.3.1.tgz",
+      "integrity": "sha1-vos2rvzN6LPKeqLWr8B6NyQsDS0=",
+      "dev": true
+    },
+    "cli-cursor": {
+      "version": "2.1.0",
+      "resolved": "https://registry.npmjs.org/cli-cursor/-/cli-cursor-2.1.0.tgz",
+      "integrity": "sha1-s12sN2R5+sw+lHR9QdDQ9SOP/LU=",
+      "dev": true
+    },
+    "cli-width": {
+      "version": "2.1.0",
+      "resolved": "https://registry.npmjs.org/cli-width/-/cli-width-2.1.0.tgz",
+      "integrity": "sha1-sjTKIJsp72b8UY2bmNWEewDt8Ao=",
+      "dev": true
+    },
+    "co": {
+      "version": "4.6.0",
+      "resolved": "https://registry.npmjs.org/co/-/co-4.6.0.tgz",
+      "integrity": "sha1-bqa989hTrlTMuOR7+gvz+QMfsYQ=",
+      "dev": true
+    },
     "concat-map": {
       "version": "https://registry.npmjs.org/concat-map/-/concat-map-0.0.1.tgz",
       "integrity": "sha1-2Klr13/Wjfd5OnMDajug1UBdR3s="
@@ -37,27 +159,493 @@
       "version": "https://registry.npmjs.org/debug/-/debug-2.2.0.tgz",
       "integrity": "sha1-+HBX6ZWxofauaklgZkE3vFbwOdo="
     },
+    "deep-is": {
+      "version": "0.1.3",
+      "resolved": "https://registry.npmjs.org/deep-is/-/deep-is-0.1.3.tgz",
+      "integrity": "sha1-s2nW+128E+7PUk+RsHD+7cNXzzQ=",
+      "dev": true
+    },
+    "del": {
+      "version": "2.2.2",
+      "resolved": "https://registry.npmjs.org/del/-/del-2.2.2.tgz",
+      "integrity": "sha1-wSyYHQZ4RshLyvhiz/kw2Qf/0ag=",
+      "dev": true,
+      "dependencies": {
+        "balanced-match": {
+          "version": "1.0.0",
+          "resolved": "https://registry.npmjs.org/balanced-match/-/balanced-match-1.0.0.tgz",
+          "integrity": "sha1-ibTRmasr7kneFk6gK4nORi1xt2c=",
+          "dev": true
+        },
+        "brace-expansion": {
+          "version": "1.1.8",
+          "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.8.tgz",
+          "integrity": "sha1-wHshHHyVLsH479Uad+8NHTmQopI=",
+          "dev": true
+        },
+        "concat-map": {
+          "version": "0.0.1",
+          "resolved": "https://registry.npmjs.org/concat-map/-/concat-map-0.0.1.tgz",
+          "integrity": "sha1-2Klr13/Wjfd5OnMDajug1UBdR3s=",
+          "dev": true
+        },
+        "fs.realpath": {
+          "version": "1.0.0",
+          "resolved": "https://registry.npmjs.org/fs.realpath/-/fs.realpath-1.0.0.tgz",
+          "integrity": "sha1-FQStJSMVjKpA20onh8sBQRmU6k8=",
+          "dev": true
+        },
+        "glob": {
+          "version": "7.1.2",
+          "resolved": "https://registry.npmjs.org/glob/-/glob-7.1.2.tgz",
+          "integrity": "sha512-MJTUg1kjuLeQCJ+ccE4Vpa6kKVXkPYJ2mOCQyUuKLcLQsdrMCpBPUi8qVE6+YuaJkozeA9NusTAw3hLr8Xe5EQ==",
+          "dev": true
+        },
+        "inflight": {
+          "version": "1.0.6",
+          "resolved": "https://registry.npmjs.org/inflight/-/inflight-1.0.6.tgz",
+          "integrity": "sha1-Sb1jMdfQLQwJvJEKEHW6gWW1bfk=",
+          "dev": true
+        },
+        "inherits": {
+          "version": "2.0.3",
+          "resolved": "https://registry.npmjs.org/inherits/-/inherits-2.0.3.tgz",
+          "integrity": "sha1-Yzwsg+PaQqUC9SRmAiSA9CCCYd4=",
+          "dev": true
+        },
+        "minimatch": {
+          "version": "3.0.4",
+          "resolved": "https://registry.npmjs.org/minimatch/-/minimatch-3.0.4.tgz",
+          "integrity": "sha512-yJHVQEhyqPLUTgt9B83PXu6W3rx4MvvHvSUvToogpwoGDOUQ+yDrR0HRot+yOCdCO7u4hX3pWft6kWBBcqh0UA==",
+          "dev": true
+        },
+        "once": {
+          "version": "1.4.0",
+          "resolved": "https://registry.npmjs.org/once/-/once-1.4.0.tgz",
+          "integrity": "sha1-WDsap3WWHUsROsF9nFC6753Xa9E=",
+          "dev": true
+        },
+        "path-is-absolute": {
+          "version": "1.0.1",
+          "resolved": "https://registry.npmjs.org/path-is-absolute/-/path-is-absolute-1.0.1.tgz",
+          "integrity": "sha1-F0uSaHNVNP+8es5r9TpanhtcX18=",
+          "dev": true
+        },
+        "rimraf": {
+          "version": "2.6.1",
+          "resolved": "https://registry.npmjs.org/rimraf/-/rimraf-2.6.1.tgz",
+          "integrity": "sha1-wjOOxkPfeht/5cVPqG9XQopV8z0=",
+          "dev": true
+        },
+        "wrappy": {
+          "version": "1.0.2",
+          "resolved": "https://registry.npmjs.org/wrappy/-/wrappy-1.0.2.tgz",
+          "integrity": "sha1-tSQ9jz7BqjXxNkYFvA0QNuMKtp8=",
+          "dev": true
+        }
+      }
+    },
+    "doctrine": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/doctrine/-/doctrine-2.0.0.tgz",
+      "integrity": "sha1-xz2NKQnSIpHhoAejlYBNqLZl/mM=",
+      "dev": true,
+      "dependencies": {
+        "isarray": {
+          "version": "1.0.0",
+          "resolved": "https://registry.npmjs.org/isarray/-/isarray-1.0.0.tgz",
+          "integrity": "sha1-u5NdSFgsuhaMBoNJV6VKPgcSTxE=",
+          "dev": true
+        }
+      }
+    },
+    "escape-string-regexp": {
+      "version": "1.0.5",
+      "resolved": "https://registry.npmjs.org/escape-string-regexp/-/escape-string-regexp-1.0.5.tgz",
+      "integrity": "sha1-G2HAViGQqN/2rjuyzwIAyhMLhtQ=",
+      "dev": true
+    },
+    "eslint": {
+      "version": "4.0.0",
+      "resolved": "https://registry.npmjs.org/eslint/-/eslint-4.0.0.tgz",
+      "integrity": "sha1-cnfAFDf99B3M0WjVqg5Jt1yh8mA=",
+      "dev": true,
+      "dependencies": {
+        "balanced-match": {
+          "version": "1.0.0",
+          "resolved": "https://registry.npmjs.org/balanced-match/-/balanced-match-1.0.0.tgz",
+          "integrity": "sha1-ibTRmasr7kneFk6gK4nORi1xt2c=",
+          "dev": true
+        },
+        "brace-expansion": {
+          "version": "1.1.8",
+          "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.8.tgz",
+          "integrity": "sha1-wHshHHyVLsH479Uad+8NHTmQopI=",
+          "dev": true
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+    },
+    "json-stable-stringify": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/json-stable-stringify/-/json-stable-stringify-1.0.1.tgz",
+      "integrity": "sha1-mnWdOcXy/1A/1TAGRu1EX4jE+a8=",
+      "dev": true
+    },
+    "jsonify": {
+      "version": "0.0.0",
+      "resolved": "https://registry.npmjs.org/jsonify/-/jsonify-0.0.0.tgz",
+      "integrity": "sha1-LHS27kHZPKUbe1qu6PUDYx0lKnM=",
+      "dev": true
+    },
+    "jsonpointer": {
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/jsonpointer/-/jsonpointer-4.0.1.tgz",
+      "integrity": "sha1-T9kss04OnbPInIYi7PUfm5eMbLk=",
+      "dev": true
+    },
+    "levn": {
+      "version": "0.3.0",
+      "resolved": "https://registry.npmjs.org/levn/-/levn-0.3.0.tgz",
+      "integrity": "sha1-OwmSTt+fCDwEkP3UwLxEIeBHZO4=",
+      "dev": true
+    },
+    "lodash": {
+      "version": "4.17.4",
+      "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.4.tgz",
+      "integrity": "sha1-eCA6TRwyiuHYbcpkYONptX9AVa4=",
+      "dev": true
+    },
     "mime": {
       "version": "https://registry.npmjs.org/mime/-/mime-1.3.6.tgz",
       "integrity": "sha1-WR2E02U6awtKO5343lqoEI5y5eA="
     },
+    "mimic-fn": {
+      "version": "1.1.0",
+      "resolved": "https://registry.npmjs.org/mimic-fn/-/mimic-fn-1.1.0.tgz",
+      "integrity": "sha1-5md4PZLonb00KBi1IwudYqZyrRg=",
+      "dev": true
+    },
     "minimatch": {
       "version": "https://registry.npmjs.org/minimatch/-/minimatch-3.0.4.tgz",
       "integrity": "sha1-UWbihkV/AzBgZL5Ul+jbsMPTIIM="
@@ -107,40 +803,112 @@
       "version": "https://registry.npmjs.org/ms/-/ms-0.7.1.tgz",
       "integrity": "sha1-nNE8A62/8ltl7/3nzoZO6VIBcJg="
     },
+    "mute-stream": {
+      "version": "0.0.7",
+      "resolved": "https://registry.npmjs.org/mute-stream/-/mute-stream-0.0.7.tgz",
+      "integrity": "sha1-MHXOk7whuPq0PhvE2n6BFe0ee6s=",
+      "dev": true
+    },
     "nan": {
       "version": "https://registry.npmjs.org/nan/-/nan-2.6.2.tgz",
       "integrity": "sha1-5P805slf37WuzAjeZZb0NgWn20U=",
       "dev": true
     },
+    "natural-compare": {
+      "version": "1.4.0",
+      "resolved": "https://registry.npmjs.org/natural-compare/-/natural-compare-1.4.0.tgz",
+      "integrity": "sha1-Sr6/7tdUHywnrPspvbvRXI1bpPc=",
+      "dev": true
+    },
     "ncp": {
       "version": "https://registry.npmjs.org/ncp/-/ncp-2.0.0.tgz",
       "integrity": "sha1-GVoh1sRuNh0vsSgbo4uR6d9727M=",
       "dev": true
     },
+    "object-assign": {
+      "version": "4.1.1",
+      "resolved": "https://registry.npmjs.org/object-assign/-/object-assign-4.1.1.tgz",
+      "integrity": "sha1-IQmtx5ZYh8/AXLvUQsrIv7s2CGM=",
+      "dev": true
+    },
     "once": {
       "version": "https://registry.npmjs.org/once/-/once-1.4.0.tgz",
       "integrity": "sha1-WDsap3WWHUsROsF9nFC6753Xa9E="
     },
+    "onetime": {
+      "version": "2.0.1",
+      "resolved": "https://registry.npmjs.org/onetime/-/onetime-2.0.1.tgz",
+      "integrity": "sha1-BnQoIw/WdEOyeUsiu6UotoZ5YtQ=",
+      "dev": true
+    },
+    "optionator": {
+      "version": "0.8.2",
+      "resolved": "https://registry.npmjs.org/optionator/-/optionator-0.8.2.tgz",
+      "integrity": "sha1-NkxeQJ0/TWMB1sC0wFu6UBgK62Q=",
+      "dev": true
+    },
+    "os-tmpdir": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/os-tmpdir/-/os-tmpdir-1.0.2.tgz",
+      "integrity": "sha1-u+Z0BseaqFxc/sdm/lc0VV36EnQ=",
+      "dev": true
+    },
     "path-is-absolute": {
       "version": "https://registry.npmjs.org/path-is-absolute/-/path-is-absolute-1.0.1.tgz",
       "integrity": "sha1-F0uSaHNVNP+8es5r9TpanhtcX18="
     },
+    "path-is-inside": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/path-is-inside/-/path-is-inside-1.0.2.tgz",
+      "integrity": "sha1-NlQX3t5EQw0cEa9hAn+s8HS9/FM=",
+      "dev": true
+    },
     "pend": {
       "version": "https://registry.npmjs.org/pend/-/pend-1.2.0.tgz",
       "integrity": "sha1-elfrVQpng/kRUzH89GY9XI4AelA="
     },
+    "pify": {
+      "version": "2.3.0",
+      "resolved": "https://registry.npmjs.org/pify/-/pify-2.3.0.tgz",
+      "integrity": "sha1-7RQaasBDqEnqWISY59yosVMw6Qw=",
+      "dev": true
+    },
+    "pinkie": {
+      "version": "2.0.4",
+      "resolved": "https://registry.npmjs.org/pinkie/-/pinkie-2.0.4.tgz",
+      "integrity": "sha1-clVrgM+g1IqXToDnckjoDtT3+HA=",
+      "dev": true
+    },
+    "pinkie-promise": {
+      "version": "2.0.1",
+      "resolved": "https://registry.npmjs.org/pinkie-promise/-/pinkie-promise-2.0.1.tgz",
+      "integrity": "sha1-ITXW36ejWMBprJsXh3YogihFD/o=",
+      "dev": true
+    },
     "pixelmatch": {
       "version": "4.0.2",
       "resolved": "https://registry.npmjs.org/pixelmatch/-/pixelmatch-4.0.2.tgz",
       "integrity": "sha1-j0fc7FARtHe2fbA8JDvB8wheiFQ=",
       "dev": true
     },
+    "pluralize": {
+      "version": "4.0.0",
+      "resolved": "https://registry.npmjs.org/pluralize/-/pluralize-4.0.0.tgz",
+      "integrity": "sha1-WbcIwcAZCi9pLxx2GMRGsFL9F2I=",
+      "dev": true
+    },
     "pngjs": {
       "version": "3.2.0",
       "resolved": "https://registry.npmjs.org/pngjs/-/pngjs-3.2.0.tgz",
       "integrity": "sha1-/J/OoaijddpUpRFIAZ1avUHbq94=",
       "dev": true
     },
+    "prelude-ls": {
+      "version": "1.1.2",
+      "resolved": "https://registry.npmjs.org/prelude-ls/-/prelude-ls-1.1.2.tgz",
+      "integrity": "sha1-IZMqVJ9eUv/ZqCf1cOBL5iqX2lQ=",
+      "dev": true
+    },
     "process-nextick-args": {
       "version": "https://registry.npmjs.org/process-nextick-args/-/process-nextick-args-1.0.7.tgz",
       "integrity": "sha1-FQ4gt1ZZCtP5EJPyWk8q2L/zC6M="
@@ -153,24 +921,138 @@
       "version": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.2.11.tgz",
       "integrity": "sha1-B5azH412iAB/8Lk6gIjTSqF8D3I="
     },
+    "require-uncached": {
+      "version": "1.0.3",
+      "resolved": "https://registry.npmjs.org/require-uncached/-/require-uncached-1.0.3.tgz",
+      "integrity": "sha1-Tg1W1slmL9MeQwEcS5WqSZVUIdM=",
+      "dev": true
+    },
+    "resolve-from": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/resolve-from/-/resolve-from-1.0.1.tgz",
+      "integrity": "sha1-Jsv+k10a7uq7Kbw/5a6wHpPUQiY=",
+      "dev": true
+    },
+    "restore-cursor": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/restore-cursor/-/restore-cursor-2.0.0.tgz",
+      "integrity": "sha1-n37ih/gv0ybU/RYpI9YhKe7g368=",
+      "dev": true
+    },
     "rimraf": {
       "version": "https://registry.npmjs.org/rimraf/-/rimraf-2.6.1.tgz",
       "integrity": "sha1-wjOOxkPfeht/5cVPqG9XQopV8z0="
     },
+    "run-async": {
+      "version": "2.3.0",
+      "resolved": "https://registry.npmjs.org/run-async/-/run-async-2.3.0.tgz",
+      "integrity": "sha1-A3GrSuC91yDUFm19/aZP96RFpsA=",
+      "dev": true
+    },
+    "rx-lite": {
+      "version": "4.0.8",
+      "resolved": "https://registry.npmjs.org/rx-lite/-/rx-lite-4.0.8.tgz",
+      "integrity": "sha1-Cx4Rr4vESDbwSmQH6S2kJGe3lEQ=",
+      "dev": true
+    },
+    "rx-lite-aggregates": {
+      "version": "4.0.8",
+      "resolved": "https://registry.npmjs.org/rx-lite-aggregates/-/rx-lite-aggregates-4.0.8.tgz",
+      "integrity": "sha1-dTuHqJoRyVRnxKwWJsTvxOBcZ74=",
+      "dev": true
+    },
     "safe-buffer": {
       "version": "https://registry.npmjs.org/safe-buffer/-/safe-buffer-5.0.1.tgz",
       "integrity": "sha1-0mPKVGls2KMGtcplUekt5XkY++c="
     },
+    "signal-exit": {
+      "version": "3.0.2",
+      "resolved": "https://registry.npmjs.org/signal-exit/-/signal-exit-3.0.2.tgz",
+      "integrity": "sha1-tf3AjxKH6hF4Yo5BXiUTK3NkbG0=",
+      "dev": true
+    },
+    "slice-ansi": {
+      "version": "0.0.4",
+      "resolved": "https://registry.npmjs.org/slice-ansi/-/slice-ansi-0.0.4.tgz",
+      "integrity": "sha1-7b+JA/ZvfOL46v1s7tZeJkyDGzU=",
+      "dev": true
+    },
+    "sprintf-js": {
+      "version": "1.0.3",
+      "resolved": "https://registry.npmjs.org/sprintf-js/-/sprintf-js-1.0.3.tgz",
+      "integrity": "sha1-BOaSb2YolTVPPdAVIDYzuFcpfiw=",
+      "dev": true
+    },
     "string_decoder": {
       "version": "https://registry.npmjs.org/string_decoder/-/string_decoder-1.0.2.tgz",
       "integrity": "sha1-sp4fThEl+pehA4K4pTNze3SR4Xk="
     },
+    "string-width": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/string-width/-/string-width-2.0.0.tgz",
+      "integrity": "sha1-Y1xUNsxypuDDh87KJ41OLuxSaH4=",
+      "dev": true
+    },
+    "strip-ansi": {
+      "version": "3.0.1",
+      "resolved": "https://registry.npmjs.org/strip-ansi/-/strip-ansi-3.0.1.tgz",
+      "integrity": "sha1-ajhfuIU9lS1f8F0Oiq+UJ43GPc8=",
+      "dev": true
+    },
+    "strip-json-comments": {
+      "version": "2.0.1",
+      "resolved": "https://registry.npmjs.org/strip-json-comments/-/strip-json-comments-2.0.1.tgz",
+      "integrity": "sha1-PFMZQukIwml8DsNEhYwobHygpgo=",
+      "dev": true
+    },
+    "supports-color": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/supports-color/-/supports-color-2.0.0.tgz",
+      "integrity": "sha1-U10EXOa2Nj+kARcIRimZXp3zJMc=",
+      "dev": true
+    },
+    "table": {
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/table/-/table-4.0.1.tgz",
+      "integrity": "sha1-qBFsEz+sLGH0pCCrbN9cTWHw5DU=",
+      "dev": true
+    },
     "text-diff": {
       "version": "1.0.1",
       "resolved": "https://registry.npmjs.org/text-diff/-/text-diff-1.0.1.tgz",
       "integrity": "sha1-bBBZBUNeM3hXN1ydL2ymPkU/9WU=",
       "dev": true
     },
+    "text-table": {
+      "version": "0.2.0",
+      "resolved": "https://registry.npmjs.org/text-table/-/text-table-0.2.0.tgz",
+      "integrity": "sha1-f17oI66AUgfACvLfSoTsP8+lcLQ=",
+      "dev": true
+    },
+    "through": {
+      "version": "2.3.8",
+      "resolved": "https://registry.npmjs.org/through/-/through-2.3.8.tgz",
+      "integrity": "sha1-DdTJ/6q8NXlgsbckEV1+Doai4fU=",
+      "dev": true
+    },
+    "tmp": {
+      "version": "0.0.31",
+      "resolved": "https://registry.npmjs.org/tmp/-/tmp-0.0.31.tgz",
+      "integrity": "sha1-jzirlDjhcxXl29izZX6L+yd65Kc=",
+      "dev": true
+    },
+    "tryit": {
+      "version": "1.0.3",
+      "resolved": "https://registry.npmjs.org/tryit/-/tryit-1.0.3.tgz",
+      "integrity": "sha1-OTvnMKlEb9Hq1tpZoBQwjzbCics=",
+      "dev": true
+    },
+    "type-check": {
+      "version": "0.3.2",
+      "resolved": "https://registry.npmjs.org/type-check/-/type-check-0.3.2.tgz",
+      "integrity": "sha1-WITKtRLPHTVeP7eE8wgEsrUg23I=",
+      "dev": true
+    },
     "typedarray": {
       "version": "https://registry.npmjs.org/typedarray/-/typedarray-0.0.6.tgz",
       "integrity": "sha1-hnrHTjhkGHsdPUfZlqeOxciDB3c="
@@ -184,15 +1066,47 @@
       "version": "https://registry.npmjs.org/util-deprecate/-/util-deprecate-1.0.2.tgz",
       "integrity": "sha1-RQ1Nyfpw3nMnYvvS1KKJgUGaDM8="
     },
+    "wordwrap": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/wordwrap/-/wordwrap-1.0.0.tgz",
+      "integrity": "sha1-J1hIEIkUVqQXHI0CJkQa3pDLyus=",
+      "dev": true
+    },
     "wrappy": {
       "version": "https://registry.npmjs.org/wrappy/-/wrappy-1.0.2.tgz",
       "integrity": "sha1-tSQ9jz7BqjXxNkYFvA0QNuMKtp8="
     },
+    "write": {
+      "version": "0.2.1",
+      "resolved": "https://registry.npmjs.org/write/-/write-0.2.1.tgz",
+      "integrity": "sha1-X8A4KOJkzqP+kUVUdvejxWbLB1c=",
+      "dev": true,
+      "dependencies": {
+        "minimist": {
+          "version": "0.0.8",
+          "resolved": "https://registry.npmjs.org/minimist/-/minimist-0.0.8.tgz",
+          "integrity": "sha1-hX/Kv8M5fSYluCKCYuhqp6ARsF0=",
+          "dev": true
+        },
+        "mkdirp": {
+          "version": "0.5.1",
+          "resolved": "https://registry.npmjs.org/mkdirp/-/mkdirp-0.5.1.tgz",
+          "integrity": "sha1-MAV0OOrGz3+MR2fzhkjWaX11yQM=",
+          "dev": true
+        }
+      }
+    },
     "ws": {
       "version": "3.0.0",
       "resolved": "https://registry.npmjs.org/ws/-/ws-3.0.0.tgz",
       "integrity": "sha1-mN2wAFbIOQy3Ued4h4hJf5kQO2w="
     },
+    "xtend": {
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/xtend/-/xtend-4.0.1.tgz",
+      "integrity": "sha1-pcbVMr5lbiPbgg77lDofBJmNY68=",
+      "dev": true
+    },
     "yauzl": {
       "version": "https://registry.npmjs.org/yauzl/-/yauzl-2.4.1.tgz",
       "integrity": "sha1-lSj0QtqxsihOWLQ3m7GU4i4MQAU="
diff --git a/phantom_shim/FileSystem.js b/phantom_shim/FileSystem.js
index f25cf7f72a7..f96ddfdbc3d 100644
--- a/phantom_shim/FileSystem.js
+++ b/phantom_shim/FileSystem.js
@@ -21,355 +21,355 @@ var removeRecursive = require('rimraf').sync;
 var copyRecursive = deasync(require('ncp').ncp);
 
 class FileSystem {
-    constructor() {
-        this.separator = path.sep;
-    }
+  constructor() {
+    this.separator = path.sep;
+  }
 
-    /**
-     * @return {string}
-     */
-    get workingDirectory() {
-        return process.cwd();
-    }
+  /**
+   * @return {string}
+   */
+  get workingDirectory() {
+    return process.cwd();
+  }
 
-    /**
-     * @param {string} directoryPath
-     */
-    changeWorkingDirectory(directoryPath) {
-        try {
-            process.chdir(directoryPath);
-            return true;
-        } catch (e){
-            return false;
-        }
+  /**
+   * @param {string} directoryPath
+   */
+  changeWorkingDirectory(directoryPath) {
+    try {
+      process.chdir(directoryPath);
+      return true;
+    } catch (e){
+      return false;
     }
+  }
 
-    /**
-     * @param {string} relativePath
-     * @return {string}
-     */
-    absolute(relativePath) {
-        relativePath = path.normalize(relativePath);
-        if (path.isAbsolute(relativePath))
-            return relativePath;
-        return path.resolve(path.join(process.cwd(), relativePath));
-    }
+  /**
+   * @param {string} relativePath
+   * @return {string}
+   */
+  absolute(relativePath) {
+    relativePath = path.normalize(relativePath);
+    if (path.isAbsolute(relativePath))
+      return relativePath;
+    return path.resolve(path.join(process.cwd(), relativePath));
+  }
 
-    /**
-     * @param {string} filePath
-     * @return {boolean}
-     */
-    exists(filePath) {
-        return fs.existsSync(filePath);
-    }
+  /**
+   * @param {string} filePath
+   * @return {boolean}
+   */
+  exists(filePath) {
+    return fs.existsSync(filePath);
+  }
 
-    /**
-     * @param {string} fromPath
-     * @param {string} toPath
-     */
-    copy(fromPath, toPath) {
-        var content = fs.readFileSync(fromPath);
-        fs.writeFileSync(toPath, content);
-    }
+  /**
+   * @param {string} fromPath
+   * @param {string} toPath
+   */
+  copy(fromPath, toPath) {
+    var content = fs.readFileSync(fromPath);
+    fs.writeFileSync(toPath, content);
+  }
 
-    /**
-     * @param {string} fromPath
-     * @param {string} toPath
-     */
-    move(fromPath, toPath) {
-        var content = fs.readFileSync(fromPath);
-        fs.writeFileSync(toPath, content);
-        fs.unlinkSync(fromPath);
-    }
+  /**
+   * @param {string} fromPath
+   * @param {string} toPath
+   */
+  move(fromPath, toPath) {
+    var content = fs.readFileSync(fromPath);
+    fs.writeFileSync(toPath, content);
+    fs.unlinkSync(fromPath);
+  }
 
-    /**
-     * @param {string} filePath
-     * @return {number}
-     */
-    size(filePath) {
-        return fs.statSync(filePath).size;
-    }
+  /**
+   * @param {string} filePath
+   * @return {number}
+   */
+  size(filePath) {
+    return fs.statSync(filePath).size;
+  }
 
-    /**
-     * @param {string} filePath
-     */
-    touch(filePath) {
-        fs.closeSync(fs.openSync(filePath, 'a'));
-    }
+  /**
+   * @param {string} filePath
+   */
+  touch(filePath) {
+    fs.closeSync(fs.openSync(filePath, 'a'));
+  }
 
-    /**
-     * @param {string} filePath
-     */
-    remove(filePath) {
-        fs.unlinkSync(filePath);
-    }
+  /**
+   * @param {string} filePath
+   */
+  remove(filePath) {
+    fs.unlinkSync(filePath);
+  }
 
-    /**
-     * @param {string} filePath
-     * @return {boolean}
-     */
-    lastModified(filePath) {
-        return fs.statSync(filePath).mtime;
-    }
+  /**
+   * @param {string} filePath
+   * @return {boolean}
+   */
+  lastModified(filePath) {
+    return fs.statSync(filePath).mtime;
+  }
 
-    /**
-     * @param {string} dirPath
-     * @return {boolean}
-     */
-    makeDirectory(dirPath) {
-        try {
-            fs.mkdirSync(dirPath);
-            return true;
-        } catch (e) {
-            return false;
-        }
+  /**
+   * @param {string} dirPath
+   * @return {boolean}
+   */
+  makeDirectory(dirPath) {
+    try {
+      fs.mkdirSync(dirPath);
+      return true;
+    } catch (e) {
+      return false;
     }
+  }
 
-    /**
-     * @param {string} dirPath
-     * @return {boolean}
-     */
-    makeTree(dirPath) {
-        return this.makeDirectory(dirPath);
-    }
+  /**
+   * @param {string} dirPath
+   * @return {boolean}
+   */
+  makeTree(dirPath) {
+    return this.makeDirectory(dirPath);
+  }
 
-    /**
-     * @param {string} dirPath
-     */
-    removeTree(dirPath) {
-        removeRecursive(dirPath);
-    }
+  /**
+   * @param {string} dirPath
+   */
+  removeTree(dirPath) {
+    removeRecursive(dirPath);
+  }
 
-    /**
-     * @param {string} fromPath
-     * @param {string} toPath
-     */
-    copyTree(fromPath, toPath) {
-        copyRecursive(fromPath, toPath);
-    }
+  /**
+   * @param {string} fromPath
+   * @param {string} toPath
+   */
+  copyTree(fromPath, toPath) {
+    copyRecursive(fromPath, toPath);
+  }
 
-    /**
-     * @param {string} dirPath
-     * @return {!Array<string>}
-     */
-    list(dirPath) {
-        return fs.readdirSync(dirPath);
-    }
+  /**
+   * @param {string} dirPath
+   * @return {!Array<string>}
+   */
+  list(dirPath) {
+    return fs.readdirSync(dirPath);
+  }
 
-    /**
-     * @param {string} linkPath
-     * @return {string}
-     */
-    readLink(linkPath) {
-        return fs.readlinkSync(linkPath);
-    }
+  /**
+   * @param {string} linkPath
+   * @return {string}
+   */
+  readLink(linkPath) {
+    return fs.readlinkSync(linkPath);
+  }
 
-    /**
-     * @param {string} filePath
-     * @param {Object} data
-     * @param {string} mode
-     */
-    write(filePath, data, mode) {
-        var fd = new FileDescriptor(filePath, mode, 'utf8');
-        fd.write(data);
-        fd.close();
-    }
+  /**
+   * @param {string} filePath
+   * @param {Object} data
+   * @param {string} mode
+   */
+  write(filePath, data, mode) {
+    var fd = new FileDescriptor(filePath, mode, 'utf8');
+    fd.write(data);
+    fd.close();
+  }
 
-    /**
-     * @param {string} somePath
-     * @return {boolean}
-     */
-    isAbsolute(somePath) {
-        return path.isAbsolute(somePath);
-    }
+  /**
+   * @param {string} somePath
+   * @return {boolean}
+   */
+  isAbsolute(somePath) {
+    return path.isAbsolute(somePath);
+  }
 
-    /**
-     * @return {string}
-     */
-    read(filePath) {
-        return fs.readFileSync(filePath, 'utf8');
-    }
+  /**
+   * @return {string}
+   */
+  read(filePath) {
+    return fs.readFileSync(filePath, 'utf8');
+  }
 
-    /**
-     * @param {string} filePath
-     * @return {boolean}
-     */
-    isFile(filePath) {
-        return fs.existsSync(filePath) && fs.lstatSync(filePath).isFile();
-    }
+  /**
+   * @param {string} filePath
+   * @return {boolean}
+   */
+  isFile(filePath) {
+    return fs.existsSync(filePath) && fs.lstatSync(filePath).isFile();
+  }
 
-    /**
-     * @param {string} dirPath
-     * @return {boolean}
-     */
-    isDirectory(dirPath) {
-        return fs.existsSync(dirPath) && fs.lstatSync(dirPath).isDirectory();
-    }
+  /**
+   * @param {string} dirPath
+   * @return {boolean}
+   */
+  isDirectory(dirPath) {
+    return fs.existsSync(dirPath) && fs.lstatSync(dirPath).isDirectory();
+  }
 
-    /**
-     * @param {string} filePath
-     * @return {boolean}
-     */
-    isLink(filePath) {
-        return fs.existsSync(filePath) && fs.lstatSync(filePath).isSymbolicLink();
-    }
+  /**
+   * @param {string} filePath
+   * @return {boolean}
+   */
+  isLink(filePath) {
+    return fs.existsSync(filePath) && fs.lstatSync(filePath).isSymbolicLink();
+  }
 
-    /**
-     * @param {string} filePath
-     * @return {boolean}
-     */
-    isReadable(filePath) {
-        try {
-            fs.accessSync(filePath, fs.constants.R_OK);
-            return true;
-        } catch (e) {
-            return false;
-        }
+  /**
+   * @param {string} filePath
+   * @return {boolean}
+   */
+  isReadable(filePath) {
+    try {
+      fs.accessSync(filePath, fs.constants.R_OK);
+      return true;
+    } catch (e) {
+      return false;
     }
+  }
 
-    /**
-     * @param {string} filePath
-     * @return {boolean}
-     */
-    isWritable(filePath) {
-        try {
-            fs.accessSync(filePath, fs.constants.W_OK);
-            return true;
-        } catch (e) {
-            return false;
-        }
+  /**
+   * @param {string} filePath
+   * @return {boolean}
+   */
+  isWritable(filePath) {
+    try {
+      fs.accessSync(filePath, fs.constants.W_OK);
+      return true;
+    } catch (e) {
+      return false;
     }
+  }
 
-    /**
-     * @param {string} filePath
-     * @return {boolean}
-     */
-    isExecutable(filePath) {
-        try {
-            fs.accessSync(filePath, fs.constants.X_OK);
-            return true;
-        } catch (e) {
-            return false;
-        }
+  /**
+   * @param {string} filePath
+   * @return {boolean}
+   */
+  isExecutable(filePath) {
+    try {
+      fs.accessSync(filePath, fs.constants.X_OK);
+      return true;
+    } catch (e) {
+      return false;
     }
+  }
 
-    /**
-     * @param {string} somePath
-     * @return {!Array<string>}
-     */
-    split(somePath) {
-        somePath = path.normalize(somePath);
-        if (somePath.endsWith(path.sep))
-            somePath = somePath.substring(0, somePath.length - path.sep.length);
-        return somePath.split(path.sep);
-    }
+  /**
+   * @param {string} somePath
+   * @return {!Array<string>}
+   */
+  split(somePath) {
+    somePath = path.normalize(somePath);
+    if (somePath.endsWith(path.sep))
+      somePath = somePath.substring(0, somePath.length - path.sep.length);
+    return somePath.split(path.sep);
+  }
 
-    /**
-     * @param {string} path1
-     * @param {string} path2
-     * @return {string}
-     */
-    join(...args) {
-        if (args[0] === '' && args.length > 1)
-            args[0] = path.sep;
-        args = args.filter(part => typeof part === 'string');
-        return path.join.apply(path, args);
-    }
+  /**
+   * @param {string} path1
+   * @param {string} path2
+   * @return {string}
+   */
+  join(...args) {
+    if (args[0] === '' && args.length > 1)
+      args[0] = path.sep;
+    args = args.filter(part => typeof part === 'string');
+    return path.join.apply(path, args);
+  }
 
-    /**
-     * @param {string} filePath
-     * @param {(string|!Object)} option
-     * @return {!FileDescriptor}
-     */
-    open(filePath, option) {
-        if (typeof option === 'string')
-            return new FileDescriptor(filePath, option);
-        return new FileDescriptor(filePath, option.mode);
-    }
+  /**
+   * @param {string} filePath
+   * @param {(string|!Object)} option
+   * @return {!FileDescriptor}
+   */
+  open(filePath, option) {
+    if (typeof option === 'string')
+      return new FileDescriptor(filePath, option);
+    return new FileDescriptor(filePath, option.mode);
+  }
 }
 
 var fdwrite = deasync(fs.write);
 var fdread = deasync(fs.read);
 
 class FileDescriptor {
-    /**
-     * @param {string} filePath
-     * @param {string} mode
-     */
-    constructor(filePath, mode) {
-        this._position = 0;
-        this._encoding = 'utf8';
-        if (mode === 'rb') {
-            this._mode = 'r';
-            this._encoding = 'latin1';
-        } else if (mode === 'wb' || mode === 'b') {
-            this._mode = 'w';
-            this._encoding = 'latin1';
-        } else if (mode === 'rw+') {
-            this._mode = 'a+';
-            this._position = fs.existsSync(filePath) ? fs.statSync(filePath).size : 0;
-        } else {
-            this._mode = mode;
-        }
-        this._fd = fs.openSync(filePath, this._mode);
+  /**
+   * @param {string} filePath
+   * @param {string} mode
+   */
+  constructor(filePath, mode) {
+    this._position = 0;
+    this._encoding = 'utf8';
+    if (mode === 'rb') {
+      this._mode = 'r';
+      this._encoding = 'latin1';
+    } else if (mode === 'wb' || mode === 'b') {
+      this._mode = 'w';
+      this._encoding = 'latin1';
+    } else if (mode === 'rw+') {
+      this._mode = 'a+';
+      this._position = fs.existsSync(filePath) ? fs.statSync(filePath).size : 0;
+    } else {
+      this._mode = mode;
     }
+    this._fd = fs.openSync(filePath, this._mode);
+  }
 
-    /**
-     * @param {string} data
-     */
-    write(data) {
-        var buffer = Buffer.from(data, this._encoding);
-        var written = fdwrite(this._fd, buffer, 0, buffer.length, this._position);
-        this._position += written;
-    }
+  /**
+   * @param {string} data
+   */
+  write(data) {
+    var buffer = Buffer.from(data, this._encoding);
+    var written = fdwrite(this._fd, buffer, 0, buffer.length, this._position);
+    this._position += written;
+  }
 
-    getEncoding() {
-        return 'UTF-8';
-    }
+  getEncoding() {
+    return 'UTF-8';
+  }
 
-    /**
-     * @param {string} data
-     */
-    writeLine(data) {
-        this.write(data + '\n');
-    }
+  /**
+   * @param {string} data
+   */
+  writeLine(data) {
+    this.write(data + '\n');
+  }
 
-    /**
-     * @param {number=} size
-     * @return {string}
-     */
-    read(size) {
-        var position = this._position;
-        if (!size) {
-            size = fs.fstatSync(this._fd).size;
-            position = 0;
-        }
-        var buffer = new Buffer(size);
-        var bytesRead = fdread(this._fd, buffer, 0, size, position);
-        this._position += bytesRead;
-        return buffer.toString(this._encoding);
+  /**
+   * @param {number=} size
+   * @return {string}
+   */
+  read(size) {
+    var position = this._position;
+    if (!size) {
+      size = fs.fstatSync(this._fd).size;
+      position = 0;
     }
+    var buffer = new Buffer(size);
+    var bytesRead = fdread(this._fd, buffer, 0, size, position);
+    this._position += bytesRead;
+    return buffer.toString(this._encoding);
+  }
 
-    flush() {
-        // noop.
-    }
+  flush() {
+    // noop.
+  }
 
-    /**
-     * @param {number} position
-     */
-    seek(position) {
-        this._position = position;
-    }
+  /**
+   * @param {number} position
+   */
+  seek(position) {
+    this._position = position;
+  }
 
-    close() {
-        fs.closeSync(this._fd);
-    }
+  close() {
+    fs.closeSync(this._fd);
+  }
 
-    /**
-     * @return {boolean}
-     */
-    atEnd() {
-    }
+  /**
+   * @return {boolean}
+   */
+  atEnd() {
+  }
 }
 
 module.exports = FileSystem;
diff --git a/phantom_shim/Phantom.js b/phantom_shim/Phantom.js
index e1fdec631dc..e62c228bebb 100644
--- a/phantom_shim/Phantom.js
+++ b/phantom_shim/Phantom.js
@@ -24,116 +24,116 @@ var url = require('url');
  * @param {string} scriptPath
  */
 module.exports.create = function(context, scriptPath) {
-    var phantom = {
-        page: {
-            onConsoleMessage: null,
-        },
+  var phantom = {
+    page: {
+      onConsoleMessage: null,
+    },
 
-        /**
-         * @param {string} relative
-         * @param {string} base
-         * @return {string}
-         */
-        resolveRelativeUrl: function(relative, base) {
-            return url.resolve(base, relative);
-        },
+    /**
+     * @param {string} relative
+     * @param {string} base
+     * @return {string}
+     */
+    resolveRelativeUrl: function(relative, base) {
+      return url.resolve(base, relative);
+    },
 
-        /**
-         * @param {string} url
-         * @return {string}
-         */
-        fullyDecodeUrl: function(url) {
-            return decodeURI(url);
-        },
+    /**
+     * @param {string} url
+     * @return {string}
+     */
+    fullyDecodeUrl: function(url) {
+      return decodeURI(url);
+    },
 
-        libraryPath: path.dirname(scriptPath),
+    libraryPath: path.dirname(scriptPath),
 
-        onError: null,
+    onError: null,
 
-        /**
-         * @return {string}
-         */
-        get outputEncoding() {
-            return 'UTF-8';
-        },
+    /**
+     * @return {string}
+     */
+    get outputEncoding() {
+      return 'UTF-8';
+    },
 
-        /**
-         * @param {string} value
-         */
-        set outputEncoding(value) {
-            throw new Error('Phantom.outputEncoding setter is not implemented');
-        },
+    /**
+     * @param {string} value
+     */
+    set outputEncoding(value) {
+      throw new Error('Phantom.outputEncoding setter is not implemented');
+    },
 
-        /**
-         * @return {boolean}
-         */
-        get cookiesEnabled() {
-            return true;
-        },
+    /**
+     * @return {boolean}
+     */
+    get cookiesEnabled() {
+      return true;
+    },
 
-        /**
-         * @param {boolean} value
-         */
-        set cookiesEnabled(value) {
-            throw new Error('Phantom.cookiesEnabled setter is not implemented');
-        },
+    /**
+     * @param {boolean} value
+     */
+    set cookiesEnabled(value) {
+      throw new Error('Phantom.cookiesEnabled setter is not implemented');
+    },
 
-        /**
-         * @return {!{major: number, minor: number, patch: number}}
-         */
-        get version() {
-            var versionParts = require('../package.json').version.split('.');
-            return {
-                major: parseInt(versionParts[0], 10),
-                minor: parseInt(versionParts[1], 10),
-                patch: parseInt(versionParts[2], 10),
-            };
-        },
+    /**
+     * @return {!{major: number, minor: number, patch: number}}
+     */
+    get version() {
+      var versionParts = require('../package.json').version.split('.');
+      return {
+        major: parseInt(versionParts[0], 10),
+        minor: parseInt(versionParts[1], 10),
+        patch: parseInt(versionParts[2], 10),
+      };
+    },
 
-        /**
-         * @param {number=} code
-         */
-        exit: function(code) {
-            process.exit(code);
-        },
+    /**
+     * @param {number=} code
+     */
+    exit: function(code) {
+      process.exit(code);
+    },
 
-        /**
-         * @param {string} filePath
-         * @return {boolean}
-         */
-        injectJs: function(filePath) {
-            filePath = path.resolve(phantom.libraryPath, filePath);
-            if (!fs.existsSync(filePath))
-                return false;
-            var code = fs.readFileSync(filePath, 'utf8');
-            if (code.startsWith('#!'))
-                code = code.substring(code.indexOf('\n'));
-            vm.runInContext(code, context, {
-                filename: filePath,
-                displayErrors: true
-            });
-            return true;
-        },
+    /**
+     * @param {string} filePath
+     * @return {boolean}
+     */
+    injectJs: function(filePath) {
+      filePath = path.resolve(phantom.libraryPath, filePath);
+      if (!fs.existsSync(filePath))
+        return false;
+      var code = fs.readFileSync(filePath, 'utf8');
+      if (code.startsWith('#!'))
+        code = code.substring(code.indexOf('\n'));
+      vm.runInContext(code, context, {
+        filename: filePath,
+        displayErrors: true
+      });
+      return true;
+    },
 
-        /**
-         * @param {string} moduleSource
-         * @param {string} filename
-         */
-        loadModule: function(moduleSource, filename) {
-            var code = [
-                '(function(require, exports, module) {\n',
-                moduleSource,
-                '\n}.call({},',
-                'require.cache[\'' + filename + '\']._getRequire(),',
-                'require.cache[\'' + filename + '\'].exports,',
-                'require.cache[\'' + filename + '\']',
-                '));'
-            ].join('');
-            vm.runInContext(code, context, {
-                filename: filename,
-                displayErrors: true
-            });
-        },
-    };
-    return phantom;
+    /**
+     * @param {string} moduleSource
+     * @param {string} filename
+     */
+    loadModule: function(moduleSource, filename) {
+      var code = [
+        '(function(require, exports, module) {\n',
+        moduleSource,
+        '\n}.call({},',
+        'require.cache[\'' + filename + '\']._getRequire(),',
+        'require.cache[\'' + filename + '\'].exports,',
+        'require.cache[\'' + filename + '\']',
+        '));'
+      ].join('');
+      vm.runInContext(code, context, {
+        filename: filename,
+        displayErrors: true
+      });
+    },
+  };
+  return phantom;
 };
diff --git a/phantom_shim/System.js b/phantom_shim/System.js
index c6187267991..87e1d07c9a2 100644
--- a/phantom_shim/System.js
+++ b/phantom_shim/System.js
@@ -19,100 +19,100 @@ var await = require('./utilities').await;
 var os = require('os');
 
 class System {
-    /**
-     * @param {!Array<string>} args
-     */
-    constructor(args) {
-        this.args = args;
-        this.env = {};
-        Object.assign(this.env, process.env);
-        this.stdin = new StandardInput(process.stdin);
-        this.stdout = new StandardOutput(process.stdout);
-        this.stderr = new StandardOutput(process.stderr);
-        this.platform = 'phantomjs';
-        this.pid = process.pid;
-        this.isSSLSupported = false;
-        this.os = {
-            architecture: os.arch(),
-            name: os.type(),
-            version: os.release()
-        };
-    }
+  /**
+   * @param {!Array<string>} args
+   */
+  constructor(args) {
+    this.args = args;
+    this.env = {};
+    Object.assign(this.env, process.env);
+    this.stdin = new StandardInput(process.stdin);
+    this.stdout = new StandardOutput(process.stdout);
+    this.stderr = new StandardOutput(process.stderr);
+    this.platform = 'phantomjs';
+    this.pid = process.pid;
+    this.isSSLSupported = false;
+    this.os = {
+      architecture: os.arch(),
+      name: os.type(),
+      version: os.release()
+    };
+  }
 }
 
 class StandardInput {
-    /**
-     * @param {!Readable} readableStream
-     */
-    constructor(readableStream) {
-        this._readline = readline.createInterface({
-            input: readableStream
-        });
-        this._lines = [];
-        this._closed = false;
-        this._readline.on('line', line => this._lines.push(line));
-        this._readline.on('close', () => this._closed = true);
-    }
+  /**
+   * @param {!Readable} readableStream
+   */
+  constructor(readableStream) {
+    this._readline = readline.createInterface({
+      input: readableStream
+    });
+    this._lines = [];
+    this._closed = false;
+    this._readline.on('line', line => this._lines.push(line));
+    this._readline.on('close', () => this._closed = true);
+  }
 
-    /**
-     * @return {string}
-     */
-    readLine() {
-        if (this._closed && !this._lines.length)
-            return '';
-        if (!this._lines.length) {
-            var linePromise = new Promise(fulfill => this._readline.once('line', fulfill));
-            await(linePromise);
-        }
-        return this._lines.shift();
+  /**
+   * @return {string}
+   */
+  readLine() {
+    if (this._closed && !this._lines.length)
+      return '';
+    if (!this._lines.length) {
+      var linePromise = new Promise(fulfill => this._readline.once('line', fulfill));
+      await(linePromise);
     }
+    return this._lines.shift();
+  }
 
-    /**
-     * @return {string}
-     */
-    read() {
-        if (!this._closed) {
-            var closePromise = new Promise(fulfill => this._readline.once('close', fulfill));
-            await(closePromise);
-        }
-        var text = this._lines.join('\n');
-        this._lines = [];
-        return text;
+  /**
+   * @return {string}
+   */
+  read() {
+    if (!this._closed) {
+      var closePromise = new Promise(fulfill => this._readline.once('close', fulfill));
+      await(closePromise);
     }
+    var text = this._lines.join('\n');
+    this._lines = [];
+    return text;
+  }
 
-    close() {
-        this._readline.close();
-    }
+  close() {
+    this._readline.close();
+  }
 }
 
 class StandardOutput {
-    /**
-     * @param {!Writable} writableStream
-     */
-    constructor(writableStream) {
-        this._stream = writableStream;
-    }
+  /**
+   * @param {!Writable} writableStream
+   */
+  constructor(writableStream) {
+    this._stream = writableStream;
+  }
 
-    /**
-     * @param {string} data
-     */
-    write(data) {
-        this._stream.write(data);
-    }
+  /**
+   * @param {string} data
+   */
+  write(data) {
+    this._stream.write(data);
+  }
 
-    /**
-     * @param {string} data
-     */
-    writeLine(data) {
-        this._stream.write(data + '\n');
-    }
+  /**
+   * @param {string} data
+   */
+  writeLine(data) {
+    this._stream.write(data + '\n');
+  }
 
-    flush() {
-    }
+  flush() {
+  }
 
-    close() {
-        this._stream.end();
-    }
+  close() {
+    this._stream.end();
+  }
 }
 
 module.exports = System;
diff --git a/phantom_shim/WebPage.js b/phantom_shim/WebPage.js
index 6d07a5a5483..0f83541c000 100644
--- a/phantom_shim/WebPage.js
+++ b/phantom_shim/WebPage.js
@@ -23,319 +23,319 @@ var PageEvents = require('../lib/Page').Events;
 var noop = function() { };
 
 class WebPage {
-    /**
-     * @param {!Browser} browser
-     * @param {string} scriptPath
-     * @param {!Object=} options
-     */
-    constructor(browser, scriptPath, options) {
-        this._page = await(browser.newPage());
-        this.settings = new WebPageSettings(this._page);
+  /**
+   * @param {!Browser} browser
+   * @param {string} scriptPath
+   * @param {!Object=} options
+   */
+  constructor(browser, scriptPath, options) {
+    this._page = await(browser.newPage());
+    this.settings = new WebPageSettings(this._page);
 
-        options = options || {};
-        options.settings = options.settings || {};
-        if (options.settings.userAgent)
-            this.settings.userAgent = options.settings.userAgent;
-        if (options.viewportSize)
-            await(this._page.setViewportSize(options.viewportSize));
+    options = options || {};
+    options.settings = options.settings || {};
+    if (options.settings.userAgent)
+      this.settings.userAgent = options.settings.userAgent;
+    if (options.viewportSize)
+      await(this._page.setViewportSize(options.viewportSize));
 
-        this.clipRect = options.clipRect || {left: 0, top: 0, width: 0, height: 0};
-        this.onConsoleMessage = null;
-        this.onLoadFinished = null;
-        this.onResourceError = null;
-        this.onResourceReceived = null;
-        this.onInitialized = null;
-        this._deferEvaluate = false;
+    this.clipRect = options.clipRect || {left: 0, top: 0, width: 0, height: 0};
+    this.onConsoleMessage = null;
+    this.onLoadFinished = null;
+    this.onResourceError = null;
+    this.onResourceReceived = null;
+    this.onInitialized = null;
+    this._deferEvaluate = false;
 
-        this.libraryPath = path.dirname(scriptPath);
+    this.libraryPath = path.dirname(scriptPath);
 
-        this._onResourceRequestedCallback = undefined;
-        this._onConfirmCallback = undefined;
-        this._onAlertCallback = undefined;
-        this._onError = noop;
+    this._onResourceRequestedCallback = undefined;
+    this._onConfirmCallback = undefined;
+    this._onAlertCallback = undefined;
+    this._onError = noop;
 
-        this._pageEvents = new AsyncEmitter(this._page);
-        this._pageEvents.on(PageEvents.ResponseReceived, response => this._onResponseReceived(response));
-        this._pageEvents.on(PageEvents.ResourceLoadingFailed, event => (this.onResourceError || noop).call(null, event));
-        this._pageEvents.on(PageEvents.ConsoleMessage, msg => (this.onConsoleMessage || noop).call(null, msg));
-        this._pageEvents.on(PageEvents.Confirm, message => this._onConfirm(message));
-        this._pageEvents.on(PageEvents.Alert, message => this._onAlert(message));
-        this._pageEvents.on(PageEvents.Dialog, dialog => this._onDialog(dialog));
-        this._pageEvents.on(PageEvents.Error, error => (this._onError || noop).call(null, error.message, error.stack));
-    }
+    this._pageEvents = new AsyncEmitter(this._page);
+    this._pageEvents.on(PageEvents.ResponseReceived, response => this._onResponseReceived(response));
+    this._pageEvents.on(PageEvents.ResourceLoadingFailed, event => (this.onResourceError || noop).call(null, event));
+    this._pageEvents.on(PageEvents.ConsoleMessage, msg => (this.onConsoleMessage || noop).call(null, msg));
+    this._pageEvents.on(PageEvents.Confirm, message => this._onConfirm(message));
+    this._pageEvents.on(PageEvents.Alert, message => this._onAlert(message));
+    this._pageEvents.on(PageEvents.Dialog, dialog => this._onDialog(dialog));
+    this._pageEvents.on(PageEvents.Error, error => (this._onError || noop).call(null, error.message, error.stack));
+  }
+
+  /**
+   * @return {?function(!Object, !Request)}
+   */
+  get onResourceRequested() {
+    return this._onResourceRequestedCallback;
+  }
+
+  /**
+   * @return {?function(!Object, !Request)} callback
+   */
+  set onResourceRequested(callback) {
+    this._onResourceRequestedCallback = callback;
+    this._page.setRequestInterceptor(callback ? resourceInterceptor : null);
 
     /**
-     * @return {?function(!Object, !Request)}
+     * @param {!Request} request
      */
-    get onResourceRequested() {
-        return this._onResourceRequestedCallback;
+    function resourceInterceptor(request) {
+      var requestData = {
+        url: request.url(),
+        headers: request.headers()
+      };
+      callback(requestData, request);
+      if (!request.handled())
+        request.continue();
     }
+  }
 
-    /**
-     * @return {?function(!Object, !Request)} callback
-     */
-    set onResourceRequested(callback) {
-        this._onResourceRequestedCallback = callback;
-        this._page.setRequestInterceptor(callback ? resourceInterceptor : null);
-
-        /**
-         * @param {!Request} request
-         */
-        function resourceInterceptor(request) {
-            var requestData = {
-                url: request.url(),
-                headers: request.headers()
-            };
-            callback(requestData, request);
-            if (!request.handled())
-                request.continue();
-        }
+  _onResponseReceived(response) {
+    if (!this.onResourceReceived)
+      return;
+    var headers = [];
+    for (var key in response.headers) {
+      headers.push({
+        name: key,
+        value: response.headers[key]
+      });
     }
+    response.headers = headers;
+    this.onResourceReceived.call(null, response);
+  }
 
-    _onResponseReceived(response) {
-        if (!this.onResourceReceived)
-            return;
-        var headers = [];
-        for (var key in response.headers) {
-            headers.push({
-                name: key,
-                value: response.headers[key]
-            });
-        }
-        response.headers = headers;
-        this.onResourceReceived.call(null, response);
+  /**
+   * @param {string} url
+   * @param {function()} callback
+   */
+  includeJs(url, callback) {
+    this._page.addScriptTag(url).then(callback);
+  }
+
+  /**
+   * @return {!{width: number, height: number}}
+   */
+  get viewportSize() {
+    return this._page.viewportSize();
+  }
+
+  /**
+   * @return {!Object}
+   */
+  get customHeaders() {
+    return this._page.extraHTTPHeaders();
+  }
+
+  /**
+   * @param {!Object} value
+   */
+  set customHeaders(value) {
+    await(this._page.setExtraHTTPHeaders(value));
+  }
+
+  /**
+   * @param {string} filePath
+   */
+  injectJs(filePath) {
+    if (!fs.existsSync(filePath))
+      filePath = path.resolve(this.libraryPath, filePath);
+    if (!fs.existsSync(filePath))
+      return false;
+    await(this._page.injectFile(filePath));
+    return true;
+  }
+
+  /**
+   * @return {string}
+   */
+  get plainText() {
+    return await(this._page.plainText());
+  }
+
+  /**
+   * @return {string}
+   */
+  get title() {
+    return await(this._page.title());
+  }
+
+  /**
+   * @return {(function()|undefined)}
+   */
+  get onError() {
+    return this._onError;
+  }
+
+  /**
+   * @param {(function()|undefined)} handler
+   */
+  set onError(handler) {
+    if (typeof handler !== 'function')
+      handler = undefined;
+    this._onError = handler;
+  }
+
+  /**
+   * @return {(function()|undefined)}
+   */
+  get onConfirm() {
+    return this._onConfirmCallback;
+  }
+
+  /**
+   * @param {function()} handler
+   */
+  set onConfirm(handler) {
+    if (typeof handler !== 'function')
+      handler = undefined;
+    this._onConfirmCallback = handler;
+  }
+
+  /**
+   * @return {(function()|undefined)}
+   */
+  get onAlert() {
+    return this._onAlertCallback;
+  }
+
+  /**
+   * @param {function()} handler
+   */
+  set onAlert(handler) {
+    if (typeof handler !== 'function')
+      handler = undefined;
+    this._onAlertCallback = handler;
+  }
+
+  /**
+   * @param {!Dialog} dialog
+   */
+  _onDialog(dialog) {
+    if (dialog.type === 'alert' && this._onAlertCallback) {
+      this._onAlertCallback.call(null, dialog.message());
+      await(dialog.accept());
+    } else if (dialog.type === 'confirm' && this._onConfirmCallback) {
+      var result = this._onConfirmCallback.call(null, dialog.message());
+      await(result ? dialog.accept() : dialog.dismiss());
     }
+  }
 
-    /**
-     * @param {string} url
-     * @param {function()} callback
-     */
-    includeJs(url, callback) {
-        this._page.addScriptTag(url).then(callback);
-    }
+  /**
+   * @return {string}
+   */
+  get url() {
+    return await(this._page.url());
+  }
 
-    /**
-     * @return {!{width: number, height: number}}
-     */
-    get viewportSize() {
-        return this._page.viewportSize();
-    }
+  /**
+   * @param {string} html
+   */
+  set content(html) {
+    await(this._page.setContent(html));
+  }
 
-    /**
-     * @return {!Object}
-     */
-    get customHeaders() {
-        return this._page.extraHTTPHeaders();
-    }
-
-    /**
-     * @param {!Object} value
-     */
-    set customHeaders(value) {
-        await(this._page.setExtraHTTPHeaders(value));
-    }
-
-    /**
-     * @param {string} filePath
-     */
-    injectJs(filePath) {
-        if (!fs.existsSync(filePath))
-            filePath = path.resolve(this.libraryPath, filePath);
-        if (!fs.existsSync(filePath))
-            return false;
-        await(this._page.injectFile(filePath));
-        return true;
-    }
-
-    /**
-     * @return {string}
-     */
-    get plainText() {
-        return await(this._page.plainText());
-    }
-
-    /**
-     * @return {string}
-     */
-    get title() {
-        return await(this._page.title());
-    }
-
-    /**
-     * @return {(function()|undefined)}
-     */
-    get onError() {
-        return this._onError;
-    }
-
-    /**
-     * @param {(function()|undefined)} handler
-     */
-    set onError(handler) {
-        if (typeof handler !== 'function')
-            handler = undefined;
-        this._onError = handler;
-    }
-
-    /**
-     * @return {(function()|undefined)}
-     */
-    get onConfirm() {
-        return this._onConfirmCallback;
-    }
-
-    /**
-     * @param {function()} handler
-     */
-    set onConfirm(handler) {
-        if (typeof handler !== 'function')
-            handler = undefined;
-        this._onConfirmCallback = handler;
-    }
-
-    /**
-     * @return {(function()|undefined)}
-     */
-    get onAlert() {
-        return this._onAlertCallback;
-    }
-
-    /**
-     * @param {function()} handler
-     */
-    set onAlert(handler) {
-        if (typeof handler !== 'function')
-            handler = undefined;
-        this._onAlertCallback = handler;
-    }
-
-    /**
-     * @param {!Dialog} dialog
-     */
-    _onDialog(dialog) {
-        if (dialog.type === 'alert' && this._onAlertCallback) {
-            this._onAlertCallback.call(null, dialog.message());
-            await(dialog.accept());
-        } else if (dialog.type === 'confirm' && this._onConfirmCallback) {
-            var result = this._onConfirmCallback.call(null, dialog.message());
-            await(result ? dialog.accept() : dialog.dismiss());
-        }
-    }
-
-    /**
-     * @return {string}
-     */
-    get url() {
-        return await(this._page.url());
-    }
-
-    /**
-     * @param {string} html
-     */
-    set content(html) {
-        await(this._page.setContent(html));
-    }
-
-    /**
-     * @param {string} html
-     * @param {function()=} callback
-     */
-    open(url, callback) {
-        console.assert(arguments.length <= 2, 'WebPage.open does not support METHOD and DATA arguments');
-        this._deferEvaluate = true;
-        if (typeof this.onInitialized === 'function')
-            this.onInitialized();
-        this._deferEvaluate = false;
-        this._page.navigate(url).then(result => {
-            var status = result ? 'success' : 'fail';
-            if (!result) {
-                this.onResourceError.call(null, {
-                    url,
-                    errorString: 'SSL handshake failed'
-                });
-            }
-            if (this.onLoadFinished)
-                this.onLoadFinished.call(null, status);
-            if (callback)
-                callback.call(null, status);
+  /**
+   * @param {string} html
+   * @param {function()=} callback
+   */
+  open(url, callback) {
+    console.assert(arguments.length <= 2, 'WebPage.open does not support METHOD and DATA arguments');
+    this._deferEvaluate = true;
+    if (typeof this.onInitialized === 'function')
+      this.onInitialized();
+    this._deferEvaluate = false;
+    this._page.navigate(url).then(result => {
+      var status = result ? 'success' : 'fail';
+      if (!result) {
+        this.onResourceError.call(null, {
+          url,
+          errorString: 'SSL handshake failed'
         });
-    }
+      }
+      if (this.onLoadFinished)
+        this.onLoadFinished.call(null, status);
+      if (callback)
+        callback.call(null, status);
+    });
+  }
 
-    /**
-     * @param {!{width: number, height: number}} options
-     */
-    set viewportSize(options) {
-        await(this._page.setViewportSize(options));
-    }
+  /**
+   * @param {!{width: number, height: number}} options
+   */
+  set viewportSize(options) {
+    await(this._page.setViewportSize(options));
+  }
 
-    /**
-     * @param {function()} fun
-     * @param {!Array<!Object>} args
-     */
-    evaluate(fun, ...args) {
-        if (this._deferEvaluate)
-            return await(this._page.evaluateOnInitialized(fun, ...args));
-        return await(this._page.evaluate(fun, ...args));
-    }
+  /**
+   * @param {function()} fun
+   * @param {!Array<!Object>} args
+   */
+  evaluate(fun, ...args) {
+    if (this._deferEvaluate)
+      return await(this._page.evaluateOnInitialized(fun, ...args));
+    return await(this._page.evaluate(fun, ...args));
+  }
 
-    /**
-     * {string} fileName
-     */
-    render(fileName) {
-        if (fileName.endsWith('pdf')) {
-            var options = {};
-            var paperSize = this.paperSize || {};
-            options.margin = paperSize.margin;
-            options.format = paperSize.format;
-            options.landscape = paperSize.orientation === 'landscape';
-            options.width = paperSize.width;
-            options.height = paperSize.height;
-            await(this._page.printToPDF(fileName, options));
-        } else {
-            var options = {};
-            if (this.clipRect && (this.clipRect.left || this.clipRect.top || this.clipRect.width || this.clipRect.height)) {
-                options.clip = {
-                    x: this.clipRect.left,
-                    y: this.clipRect.top,
-                    width: this.clipRect.width,
-                    height: this.clipRect.height
-                };
-            }
-            options.path = fileName;
-            await(this._page.screenshot(options));
-        }
+  /**
+   * {string} fileName
+   */
+  render(fileName) {
+    if (fileName.endsWith('pdf')) {
+      var options = {};
+      var paperSize = this.paperSize || {};
+      options.margin = paperSize.margin;
+      options.format = paperSize.format;
+      options.landscape = paperSize.orientation === 'landscape';
+      options.width = paperSize.width;
+      options.height = paperSize.height;
+      await(this._page.printToPDF(fileName, options));
+    } else {
+      var options = {};
+      if (this.clipRect && (this.clipRect.left || this.clipRect.top || this.clipRect.width || this.clipRect.height)) {
+        options.clip = {
+          x: this.clipRect.left,
+          y: this.clipRect.top,
+          width: this.clipRect.width,
+          height: this.clipRect.height
+        };
+      }
+      options.path = fileName;
+      await(this._page.screenshot(options));
     }
+  }
 
-    release() {
-        this._page.close();
-    }
+  release() {
+    this._page.close();
+  }
 
-    close() {
-        this._page.close();
-    }
+  close() {
+    this._page.close();
+  }
 }
 
 class WebPageSettings {
-    /**
-     * @param {!Page} page
-     */
-    constructor(page) {
-        this._page = page;
-    }
+  /**
+   * @param {!Page} page
+   */
+  constructor(page) {
+    this._page = page;
+  }
 
-    /**
-     * @param {string} value
-     */
-    set userAgent(value) {
-        await(this._page.setUserAgentOverride(value));
-    }
+  /**
+   * @param {string} value
+   */
+  set userAgent(value) {
+    await(this._page.setUserAgentOverride(value));
+  }
 
-    /**
-     * @return {string}
-     */
-    get userAgent() {
-        return this._page.userAgentOverride();
-    }
+  /**
+   * @return {string}
+   */
+  get userAgent() {
+    return this._page.userAgentOverride();
+  }
 }
 
 // To prevent reenterability, eventemitters should emit events
@@ -349,29 +349,29 @@ class WebPageSettings {
 // This class is a wrapper around EventEmitter which re-emits events asynchronously,
 // helping to overcome the issue.
 class AsyncEmitter extends EventEmitter {
-    /**
-     * @param {!Page} page
-     */
-    constructor(page) {
-        super();
-        this._page = page;
-        this._symbol = Symbol('AsyncEmitter');
-        this.on('newListener', this._onListenerAdded);
-        this.on('removeListener', this._onListenerRemoved);
-    }
+  /**
+   * @param {!Page} page
+   */
+  constructor(page) {
+    super();
+    this._page = page;
+    this._symbol = Symbol('AsyncEmitter');
+    this.on('newListener', this._onListenerAdded);
+    this.on('removeListener', this._onListenerRemoved);
+  }
 
-    _onListenerAdded(event, listener) {
-        // Async listener calls original listener on next tick.
-        var asyncListener = (...args) => {
-            process.nextTick(() => listener.apply(null, args));
-        };
-        listener[this._symbol] = asyncListener;
-        this._page.on(event, asyncListener);
-    }
+  _onListenerAdded(event, listener) {
+    // Async listener calls original listener on next tick.
+    var asyncListener = (...args) => {
+      process.nextTick(() => listener.apply(null, args));
+    };
+    listener[this._symbol] = asyncListener;
+    this._page.on(event, asyncListener);
+  }
 
-    _onListenerRemoved(event, listener) {
-        this._page.removeListener(event, listener[this._symbol]);
-    }
+  _onListenerRemoved(event, listener) {
+    this._page.removeListener(event, listener[this._symbol]);
+  }
 }
 
 module.exports = WebPage;
diff --git a/phantom_shim/WebServer.js b/phantom_shim/WebServer.js
index 320243f46d6..b5e151c5645 100644
--- a/phantom_shim/WebServer.js
+++ b/phantom_shim/WebServer.js
@@ -18,66 +18,66 @@ var http = require('http');
 var await = require('./utilities').await;
 
 class WebServer {
-    constructor() {
-        this._server = http.createServer();
-        this.objectName = 'WebServer';
-        this.listenOnPort = this.listen;
-        this.newRequest = function(req, res) { };
-        Object.defineProperty(this, 'port', {
-            get: () => {
-                if (!this._server.listening)
-                    return '';
-                return this._server.address().port + '';
-            },
-            enumerable: true,
-            configurable: false
-        });
-    }
-
-    close() {
-        this._server.close();
-    }
-
-    /**
-     * @param {nubmer} port
-     * @return {boolean}
-     */
-    listen(port, callback) {
-        if (this._server.listening)
-            return false;
-        this.newRequest = callback;
-        this._server.listen(port);
-        var errorPromise = new Promise(x => this._server.once('error', x));
-        var successPromise = new Promise(x => this._server.once('listening', x));
-        await(Promise.race([errorPromise, successPromise]));
+  constructor() {
+    this._server = http.createServer();
+    this.objectName = 'WebServer';
+    this.listenOnPort = this.listen;
+    this.newRequest = function(req, res) { };
+    Object.defineProperty(this, 'port', {
+      get: () => {
         if (!this._server.listening)
-            return false;
+          return '';
+        return this._server.address().port + '';
+      },
+      enumerable: true,
+      configurable: false
+    });
+  }
 
-        this._server.on('request', (req, res) => {
-            res.close = res.end.bind(res);
-            var headers = res.getHeaders();
-            res.headers = [];
-            for (var key in headers) {
-                res.headers.push({
-                    name: key,
-                    value: headers[key]
-                });
-            }
-            res.header = res.getHeader;
-            res.setHeaders = headers => {
-                for (var key in headers)
-                    res.setHeader(key, headers[key]);
-            };
-            Object.defineProperty(res, 'statusCode', {
-                enumerable: true,
-                configurable: true,
-                writable: true,
-                value: res.statusCode
-            });
-            this.newRequest.call(null, req, res);
+  close() {
+    this._server.close();
+  }
+
+  /**
+   * @param {nubmer} port
+   * @return {boolean}
+   */
+  listen(port, callback) {
+    if (this._server.listening)
+      return false;
+    this.newRequest = callback;
+    this._server.listen(port);
+    var errorPromise = new Promise(x => this._server.once('error', x));
+    var successPromise = new Promise(x => this._server.once('listening', x));
+    await(Promise.race([errorPromise, successPromise]));
+    if (!this._server.listening)
+      return false;
+
+    this._server.on('request', (req, res) => {
+      res.close = res.end.bind(res);
+      var headers = res.getHeaders();
+      res.headers = [];
+      for (var key in headers) {
+        res.headers.push({
+          name: key,
+          value: headers[key]
         });
-        return true;
-    }
+      }
+      res.header = res.getHeader;
+      res.setHeaders = headers => {
+        for (var key in headers)
+          res.setHeader(key, headers[key]);
+      };
+      Object.defineProperty(res, 'statusCode', {
+        enumerable: true,
+        configurable: true,
+        writable: true,
+        value: res.statusCode
+      });
+      this.newRequest.call(null, req, res);
+    });
+    return true;
+  }
 }
 
 module.exports = WebServer;
diff --git a/phantom_shim/runner.js b/phantom_shim/runner.js
index 87d25fdd0d7..fc83eacb52b 100755
--- a/phantom_shim/runner.js
+++ b/phantom_shim/runner.js
@@ -27,39 +27,39 @@ var child_process = require('child_process');
 var Browser = require('..').Browser;
 var version = require('../package.json').version;
 var argv = require('minimist')(process.argv.slice(2), {
-    alias: { v: 'version' },
-    boolean: ['headless'],
-    default: {'headless': true },
+  alias: { v: 'version' },
+  boolean: ['headless'],
+  default: {'headless': true },
 });
 
 if (argv.version) {
-    console.log('Puppeteer v' + version);
-    return;
+  console.log('Puppeteer v' + version);
+  return;
 }
 
 if (argv['ssl-certificates-path']) {
-    console.error('Flag --ssl-certificates-path is not supported.');
-    process.exit(1);
-    return;
+  console.error('Flag --ssl-certificates-path is not supported.');
+  process.exit(1);
+  return;
 }
 
 var scriptArguments = argv._;
 if (!scriptArguments.length) {
-    console.log(__filename.split('/').pop() + ' [scriptfile]');
-    return;
+  console.log(__filename.split('/').pop() + ' [scriptfile]');
+  return;
 }
 
 var scriptPath = path.resolve(process.cwd(), scriptArguments[0]);
 if (!fs.existsSync(scriptPath)) {
-    console.error(`script not found: ${scriptPath}`);
-    process.exit(1);
-    return;
+  console.error(`script not found: ${scriptPath}`);
+  process.exit(1);
+  return;
 }
 
 var browser = new Browser({
-        remoteDebuggingPort: 9229,
-        headless: argv.headless,
-        args: ['--no-sandbox']
+  remoteDebuggingPort: 9229,
+  headless: argv.headless,
+  args: ['--no-sandbox']
 });
 
 var context = createPhantomContext(browser, scriptPath, argv);
@@ -73,38 +73,38 @@ vm.runInContext(scriptContent, context);
  * @return {!Object}
  */
 function createPhantomContext(browser, scriptPath, argv) {
-    var context = {};
-    context.setInterval = setInterval;
-    context.setTimeout = setTimeout;
-    context.clearInterval = clearInterval;
-    context.clearTimeout = clearTimeout;
+  var context = {};
+  context.setInterval = setInterval;
+  context.setTimeout = setTimeout;
+  context.clearInterval = clearInterval;
+  context.clearTimeout = clearTimeout;
 
-    context.phantom = Phantom.create(context, scriptPath);
-    context.console = console;
-    context.window = context;
-    context.WebPage = options => new WebPage(browser, scriptPath, options);
+  context.phantom = Phantom.create(context, scriptPath);
+  context.console = console;
+  context.window = context;
+  context.WebPage = options => new WebPage(browser, scriptPath, options);
 
-    vm.createContext(context);
+  vm.createContext(context);
 
-    var nativeExports = {
-        fs: new FileSystem(),
-        system: new System(argv._),
-        webpage: {
-            create: context.WebPage,
-        },
-        webserver: {
-            create: () => new WebServer(),
-        },
-        cookiejar: {
-            create: () => {},
-        },
-        child_process: child_process
-    };
-    var bootstrapPath = path.join(__dirname, '..', 'third_party', 'phantomjs', 'bootstrap.js');
-    var bootstrapCode = fs.readFileSync(bootstrapPath, 'utf8');
-    vm.runInContext(bootstrapCode, context, {
-        filename: 'bootstrap.js'
-    })(nativeExports);
-    return context;
+  var nativeExports = {
+    fs: new FileSystem(),
+    system: new System(argv._),
+    webpage: {
+      create: context.WebPage,
+    },
+    webserver: {
+      create: () => new WebServer(),
+    },
+    cookiejar: {
+      create: () => {},
+    },
+    child_process: child_process
+  };
+  var bootstrapPath = path.join(__dirname, '..', 'third_party', 'phantomjs', 'bootstrap.js');
+  var bootstrapCode = fs.readFileSync(bootstrapPath, 'utf8');
+  vm.runInContext(bootstrapCode, context, {
+    filename: 'bootstrap.js'
+  })(nativeExports);
+  return context;
 }
 
diff --git a/phantom_shim/utilities.js b/phantom_shim/utilities.js
index 46ee945ce7f..487ef4be71b 100644
--- a/phantom_shim/utilities.js
+++ b/phantom_shim/utilities.js
@@ -17,16 +17,16 @@
 var loopWhile = require('deasync').loopWhile;
 
 module.exports = {
-    await: function(promise) {
-        var error;
-        var result;
-        var done = false;
-        promise.then(r => result = r)
-            .catch(err => error = err)
-            .then(() => done = true);
-        loopWhile(() => !done);
-        if (error)
-            throw error;
-        return result;
-    }
+  await: function(promise) {
+    var error;
+    var result;
+    var done = false;
+    promise.then(r => result = r)
+        .catch(err => error = err)
+        .then(() => done = true);
+    loopWhile(() => !done);
+    if (error)
+      throw error;
+    return result;
+  }
 };
diff --git a/test/StaticServer.js b/test/StaticServer.js
index 6f16616c464..8cdf930c98c 100644
--- a/test/StaticServer.js
+++ b/test/StaticServer.js
@@ -21,35 +21,35 @@ var path = require('path');
 var mime = require('mime');
 
 class StaticServer {
-    /**
-     * @param {string} dirPath
-     * @param {number} port
-     */
-    constructor(dirPath, port) {
-        this._server = http.createServer(this._onRequest.bind(this));
-        this._server.listen(port);
-        this._dirPath = dirPath;
-    }
+  /**
+   * @param {string} dirPath
+   * @param {number} port
+   */
+  constructor(dirPath, port) {
+    this._server = http.createServer(this._onRequest.bind(this));
+    this._server.listen(port);
+    this._dirPath = dirPath;
+  }
 
-    stop() {
-        this._server.close();
-    }
+  stop() {
+    this._server.close();
+  }
 
-    _onRequest(request, response) {
-        var pathName = url.parse(request.url).path;
-        if (pathName === '/')
-            pathName = '/index.html';
-        pathName = path.join(this._dirPath, pathName.substring(1));
-        fs.readFile(pathName, function(err, data) {
-            if (err) {
-                response.statusCode = 404;
-                response.end(`File not found: ${pathName}`);
-                return;
-            }
-            response.setHeader('Content-Type', mime.lookup(pathName));
-            response.end(data);
-        });
-    }
+  _onRequest(request, response) {
+    var pathName = url.parse(request.url).path;
+    if (pathName === '/')
+      pathName = '/index.html';
+    pathName = path.join(this._dirPath, pathName.substring(1));
+    fs.readFile(pathName, function(err, data) {
+      if (err) {
+        response.statusCode = 404;
+        response.end(`File not found: ${pathName}`);
+        return;
+      }
+      response.setHeader('Content-Type', mime.lookup(pathName));
+      response.end(data);
+    });
+  }
 }
 
 module.exports = StaticServer;
diff --git a/test/frame-utils.js b/test/frame-utils.js
index 148f7748573..2dfc3105b94 100644
--- a/test/frame-utils.js
+++ b/test/frame-utils.js
@@ -1,62 +1,62 @@
 var utils = module.exports = {
-    /**
-     * @param {!Page} page
-     * @param {string} frameId
-     * @param {string} url
-     * @return {!Promise}
-     */
-    attachFrame: async function(page, frameId, url) {
-        await page.evaluate(attachFrame, frameId, url);
+  /**
+   * @param {!Page} page
+   * @param {string} frameId
+   * @param {string} url
+   * @return {!Promise}
+   */
+  attachFrame: async function(page, frameId, url) {
+    await page.evaluate(attachFrame, frameId, url);
 
-        function attachFrame(frameId, url) {
-            var frame = document.createElement('iframe');
-            frame.src = url;
-            frame.id = frameId;
-            document.body.appendChild(frame);
-            return new Promise(x => frame.onload = x);
-        }
-    },
+    function attachFrame(frameId, url) {
+      var frame = document.createElement('iframe');
+      frame.src = url;
+      frame.id = frameId;
+      document.body.appendChild(frame);
+      return new Promise(x => frame.onload = x);
+    }
+  },
 
-    /**
-     * @param {!Page} page
-     * @param {string} frameId
-     * @return {!Promise}
-     */
-    detachFrame: async function(page, frameId) {
-        await page.evaluate(detachFrame, frameId);
+  /**
+   * @param {!Page} page
+   * @param {string} frameId
+   * @return {!Promise}
+   */
+  detachFrame: async function(page, frameId) {
+    await page.evaluate(detachFrame, frameId);
 
-        function detachFrame(frameId) {
-            var frame = document.getElementById(frameId);
-            frame.remove();
-        }
-    },
+    function detachFrame(frameId) {
+      var frame = document.getElementById(frameId);
+      frame.remove();
+    }
+  },
 
-    /**
-     * @param {!Page} page
-     * @param {string} frameId
-     * @param {string} url
-     * @return {!Promise}
-     */
-    navigateFrame: async function(page, frameId, url) {
-        await page.evaluate(navigateFrame, frameId, url);
+  /**
+   * @param {!Page} page
+   * @param {string} frameId
+   * @param {string} url
+   * @return {!Promise}
+   */
+  navigateFrame: async function(page, frameId, url) {
+    await page.evaluate(navigateFrame, frameId, url);
 
-        function navigateFrame(frameId, url) {
-            var frame = document.getElementById(frameId);
-            frame.src = url;
-            return new Promise(x => frame.onload = x);
-        }
-    },
+    function navigateFrame(frameId, url) {
+      var frame = document.getElementById(frameId);
+      frame.src = url;
+      return new Promise(x => frame.onload = x);
+    }
+  },
 
-    /**
-     * @param {!Frame} frame
-     * @param {string=} indentation
-     * @return {string}
-     */
-    dumpFrames: function(frame, indentation) {
-        indentation = indentation || '';
-        var result = indentation + frame.url();
-        for (var child of frame.childFrames())
-            result += '\n' + utils.dumpFrames(child, '    ' + indentation);
-        return result;
-    },
+  /**
+   * @param {!Frame} frame
+   * @param {string=} indentation
+   * @return {string}
+   */
+  dumpFrames: function(frame, indentation) {
+    indentation = indentation || '';
+    var result = indentation + frame.url();
+    for (var child of frame.childFrames())
+      result += '\n' + utils.dumpFrames(child, '    ' + indentation);
+    return result;
+  },
 };
diff --git a/test/golden-utils.js b/test/golden-utils.js
index 55379286aa2..715a0c444e6 100644
--- a/test/golden-utils.js
+++ b/test/golden-utils.js
@@ -25,19 +25,19 @@ var GOLDEN_DIR = path.join(__dirname, 'golden');
 var OUTPUT_DIR = path.join(__dirname, 'output');
 
 module.exports = {
-    addMatchers: function(jasmine) {
-        jasmine.addMatchers(customMatchers);
-    },
+  addMatchers: function(jasmine) {
+    jasmine.addMatchers(customMatchers);
+  },
 
-    removeOutputDir: function() {
-        if (fs.existsSync(OUTPUT_DIR))
-            rm(OUTPUT_DIR);
-    },
+  removeOutputDir: function() {
+    if (fs.existsSync(OUTPUT_DIR))
+      rm(OUTPUT_DIR);
+  },
 };
 
 var GoldenComparators = {
-    'image/png': compareImages,
-    'text/plain': compareText
+  'image/png': compareImages,
+  'text/plain': compareText
 };
 
 /**
@@ -46,19 +46,19 @@ var GoldenComparators = {
  * @return {?{diff: (!Object:undefined), errorMessage: (string|undefined)}}
  */
 function compareImages(actualBuffer, expectedBuffer) {
-    if (!actualBuffer || !(actualBuffer instanceof Buffer))
-        return { errorMessage: 'Actual result should be Buffer.' };
+  if (!actualBuffer || !(actualBuffer instanceof Buffer))
+    return { errorMessage: 'Actual result should be Buffer.' };
 
-    var actual = PNG.sync.read(actualBuffer);
-    var expected = PNG.sync.read(expectedBuffer);
-    if (expected.width !== actual.width || expected.height !== actual.height) {
-        return {
-            errorMessage: `Sizes differ: expected image ${expected.width}px X ${expected.height}px, but got ${actual.width}px X ${actual.height}px. `
-        };
-    }
-    var diff = new PNG({width: expected.width, height: expected.height});
-    var count = pixelmatch(expected.data, actual.data, diff.data, expected.width, expected.height, {threshold: 0.1});
-    return count > 0 ? { diff: PNG.sync.write(diff) } : null;
+  var actual = PNG.sync.read(actualBuffer);
+  var expected = PNG.sync.read(expectedBuffer);
+  if (expected.width !== actual.width || expected.height !== actual.height) {
+    return {
+      errorMessage: `Sizes differ: expected image ${expected.width}px X ${expected.height}px, but got ${actual.width}px X ${actual.height}px. `
+    };
+  }
+  var diff = new PNG({width: expected.width, height: expected.height});
+  var count = pixelmatch(expected.data, actual.data, diff.data, expected.width, expected.height, {threshold: 0.1});
+  return count > 0 ? { diff: PNG.sync.write(diff) } : null;
 }
 
 /**
@@ -67,80 +67,80 @@ function compareImages(actualBuffer, expectedBuffer) {
  * @return {?{diff: (!Object:undefined), errorMessage: (string|undefined)}}
  */
 function compareText(actual, expectedBuffer) {
-    if (typeof actual !== 'string')
-        return { errorMessage: 'Actual result should be string' };
-    var expected = expectedBuffer.toString('utf-8');
-    if (expected === actual)
-        return null;
-    var diff = new Diff();
-    var result = diff.main(expected, actual);
-    diff.cleanupSemantic(result);
-    var html = diff.prettyHtml(result);
-    var diffStylePath = path.join(__dirname, 'diffstyle.css');
-    html = `<link rel="stylesheet" href="file://${diffStylePath}">` + html;
-    return {
-        diff: html,
-        diffExtension: '.html'
-    };
+  if (typeof actual !== 'string')
+    return { errorMessage: 'Actual result should be string' };
+  var expected = expectedBuffer.toString('utf-8');
+  if (expected === actual)
+    return null;
+  var diff = new Diff();
+  var result = diff.main(expected, actual);
+  diff.cleanupSemantic(result);
+  var html = diff.prettyHtml(result);
+  var diffStylePath = path.join(__dirname, 'diffstyle.css');
+  html = `<link rel="stylesheet" href="file://${diffStylePath}">` + html;
+  return {
+    diff: html,
+    diffExtension: '.html'
+  };
 }
 
 var customMatchers = {
-    toBeGolden: function(util, customEqualityTesters) {
+  toBeGolden: function(util, customEqualityTesters) {
+    return {
+      /**
+       * @param {?Object} actual
+       * @param {string} goldenName
+       * @return {!{pass: boolean, message: (undefined|string)}}
+       */
+      compare: function(actual, goldenName) {
+        var expectedPath = path.join(GOLDEN_DIR, goldenName);
+        var actualPath = path.join(OUTPUT_DIR, goldenName);
+
+        var messageSuffix = 'Output is saved in "' + path.basename(OUTPUT_DIR + '" directory');
+
+        if (!fs.existsSync(expectedPath)) {
+          ensureOutputDir();
+          fs.writeFileSync(actualPath, actual);
+          return {
+            pass: false,
+            message: goldenName + ' is missing in golden results. ' + messageSuffix
+          };
+        }
+        var expected = fs.readFileSync(expectedPath);
+        var comparator = GoldenComparators[mime.lookup(goldenName)];
+        if (!comparator) {
+          return {
+            pass: false,
+            message: 'Failed to find comparator with type ' + mime.lookup(goldenName) + ': '  + goldenName
+          };
+        }
+        var result = comparator(actual, expected);
+        if (!result)
+          return { pass: true };
+        ensureOutputDir();
+        fs.writeFileSync(actualPath, actual);
+        // Copy expected to the output/ folder for convenience.
+        fs.writeFileSync(addSuffix(actualPath, '-expected'), expected);
+        if (result.diff) {
+          var diffPath = addSuffix(actualPath, '-diff', result.diffExtension);
+          fs.writeFileSync(diffPath, result.diff);
+        }
+
+        var message = goldenName + ' mismatch!';
+        if (result.errorMessage)
+          message += ' ' + result.errorMessage;
         return {
-            /**
-             * @param {?Object} actual
-             * @param {string} goldenName
-             * @return {!{pass: boolean, message: (undefined|string)}}
-             */
-            compare: function(actual, goldenName) {
-                var expectedPath = path.join(GOLDEN_DIR, goldenName);
-                var actualPath = path.join(OUTPUT_DIR, goldenName);
-
-                var messageSuffix = 'Output is saved in "' + path.basename(OUTPUT_DIR + '" directory');
-
-                if (!fs.existsSync(expectedPath)) {
-                    ensureOutputDir();
-                    fs.writeFileSync(actualPath, actual);
-                    return {
-                        pass: false,
-                        message: goldenName + ' is missing in golden results. ' + messageSuffix
-                    };
-                }
-                var expected = fs.readFileSync(expectedPath);
-                var comparator = GoldenComparators[mime.lookup(goldenName)];
-                if (!comparator) {
-                    return {
-                        pass: false,
-                        message: 'Failed to find comparator with type ' + mime.lookup(goldenName) + ': '  + goldenName
-                    };
-                }
-                var result = comparator(actual, expected);
-                if (!result)
-                    return { pass: true };
-                ensureOutputDir();
-                fs.writeFileSync(actualPath, actual);
-                // Copy expected to the output/ folder for convenience.
-                fs.writeFileSync(addSuffix(actualPath, '-expected'), expected);
-                if (result.diff) {
-                    var diffPath = addSuffix(actualPath, '-diff', result.diffExtension);
-                    fs.writeFileSync(diffPath, result.diff);
-                }
-
-                var message = goldenName + ' mismatch!';
-                if (result.errorMessage)
-                    message += ' ' + result.errorMessage;
-                return {
-                    pass: false,
-                    message: message + ' ' + messageSuffix
-                };
-
-                function ensureOutputDir() {
-                    if (!fs.existsSync(OUTPUT_DIR))
-                        fs.mkdirSync(OUTPUT_DIR);
-                }
-            }
+          pass: false,
+          message: message + ' ' + messageSuffix
         };
-    },
+
+        function ensureOutputDir() {
+          if (!fs.existsSync(OUTPUT_DIR))
+            fs.mkdirSync(OUTPUT_DIR);
+        }
+      }
+    };
+  },
 };
 
 /**
@@ -150,8 +150,8 @@ var customMatchers = {
  * @return {string}
  */
 function addSuffix(filePath, suffix, customExtension) {
-    var dirname = path.dirname(filePath);
-    var ext = path.extname(filePath);
-    var name = path.basename(filePath, ext);
-    return path.join(dirname, name + suffix + (customExtension || ext));
+  var dirname = path.dirname(filePath);
+  var ext = path.extname(filePath);
+  var name = path.basename(filePath, ext);
+  return path.join(dirname, name + suffix + (customExtension || ext));
 }
diff --git a/test/test.js b/test/test.js
index 5eb330dcccf..c0154b6ae5c 100644
--- a/test/test.js
+++ b/test/test.js
@@ -26,308 +26,308 @@ var EMPTY_PAGE = STATIC_PREFIX + '/empty.html';
 jasmine.DEFAULT_TIMEOUT_INTERVAL = 10 * 1000;
 
 describe('Puppeteer', function() {
-    var browser;
-    var staticServer;
-    var page;
+  var browser;
+  var staticServer;
+  var page;
 
-    beforeAll(function() {
-        browser = new Browser({args: ['--no-sandbox']});
-        staticServer = new StaticServer(path.join(__dirname, 'assets'), PORT);
-        GoldenUtils.removeOutputDir();
-    });
+  beforeAll(function() {
+    browser = new Browser({args: ['--no-sandbox']});
+    staticServer = new StaticServer(path.join(__dirname, 'assets'), PORT);
+    GoldenUtils.removeOutputDir();
+  });
 
-    afterAll(function() {
-        browser.close();
-        staticServer.stop();
-    });
+  afterAll(function() {
+    browser.close();
+    staticServer.stop();
+  });
 
-    beforeEach(SX(async function() {
-        page = await browser.newPage();
-        GoldenUtils.addMatchers(jasmine);
+  beforeEach(SX(async function() {
+    page = await browser.newPage();
+    GoldenUtils.addMatchers(jasmine);
+  }));
+
+  afterEach(function() {
+    page.close();
+  });
+
+  describe('Page.evaluate', function() {
+    it('should work', SX(async function() {
+      var result = await page.evaluate(() => 7 * 3);
+      expect(result).toBe(21);
     }));
-
-    afterEach(function() {
-        page.close();
-    });
-
-    describe('Page.evaluate', function() {
-        it('should work', SX(async function() {
-            var result = await page.evaluate(() => 7 * 3);
-            expect(result).toBe(21);
-        }));
-        it('should await promise', SX(async function() {
-            var result = await page.evaluate(() => Promise.resolve(8 * 7));
-            expect(result).toBe(56);
-        }));
-        it('should work from-inside inPageCallback', SX(async function() {
-            // Setup inpage callback, which calls Page.evaluate
-            await page.setInPageCallback('callController', async function(a, b) {
-                return await page.evaluate((a, b) => a * b, a, b);
-            });
-            var result = await page.evaluate(async function() {
-                return await callController(9, 3);
-            });
-            expect(result).toBe(27);
-        }));
-        it('should reject promise with exception', SX(async function() {
-            var error = null;
-            try {
-                await page.evaluate(() => not.existing.object.property);
-            } catch (e) {
-                error = e;
-            }
-            expect(error).toBeTruthy();
-            expect(error.message).toContain('not is not defined');
-        }));
-    });
-
-    it('Page Events: ConsoleMessage', SX(async function() {
-        var msgs = [];
-        page.on('consolemessage', msg => msgs.push(msg));
-        await page.evaluate(() => console.log('Message!'));
-        expect(msgs).toEqual(['Message!']);
+    it('should await promise', SX(async function() {
+      var result = await page.evaluate(() => Promise.resolve(8 * 7));
+      expect(result).toBe(56);
     }));
+    it('should work from-inside inPageCallback', SX(async function() {
+      // Setup inpage callback, which calls Page.evaluate
+      await page.setInPageCallback('callController', async function(a, b) {
+        return await page.evaluate((a, b) => a * b, a, b);
+      });
+      var result = await page.evaluate(async function() {
+        return await callController(9, 3);
+      });
+      expect(result).toBe(27);
+    }));
+    it('should reject promise with exception', SX(async function() {
+      var error = null;
+      try {
+        await page.evaluate(() => not.existing.object.property);
+      } catch (e) {
+        error = e;
+      }
+      expect(error).toBeTruthy();
+      expect(error.message).toContain('not is not defined');
+    }));
+  });
 
-    describe('Page.navigate', function() {
-        it('should fail when navigating to bad url', SX(async function() {
-            var success = await page.navigate('asdfasdf');
-            expect(success).toBe(false);
-        }));
-        it('should succeed when navigating to good url', SX(async function() {
-            var success = await page.navigate(EMPTY_PAGE);
-            expect(success).toBe(true);
-        }));
+  it('Page Events: ConsoleMessage', SX(async function() {
+    var msgs = [];
+    page.on('consolemessage', msg => msgs.push(msg));
+    await page.evaluate(() => console.log('Message!'));
+    expect(msgs).toEqual(['Message!']);
+  }));
+
+  describe('Page.navigate', function() {
+    it('should fail when navigating to bad url', SX(async function() {
+      var success = await page.navigate('asdfasdf');
+      expect(success).toBe(false);
+    }));
+    it('should succeed when navigating to good url', SX(async function() {
+      var success = await page.navigate(EMPTY_PAGE);
+      expect(success).toBe(true);
+    }));
+  });
+
+  describe('Page.setInPageCallback', function() {
+    it('should work', SX(async function() {
+      await page.setInPageCallback('callController', function(a, b) {
+        return a * b;
+      });
+      var result = await page.evaluate(async function() {
+        return await callController(9, 4);
+      });
+      expect(result).toBe(36);
+    }));
+    it('should survive navigation', SX(async function() {
+      await page.setInPageCallback('callController', function(a, b) {
+        return a * b;
+      });
+
+      await page.navigate(EMPTY_PAGE);
+      var result = await page.evaluate(async function() {
+        return await callController(9, 4);
+      });
+      expect(result).toBe(36);
+    }));
+    it('should await returned promise', SX(async function() {
+      await page.setInPageCallback('callController', function(a, b) {
+        return Promise.resolve(a * b);
+      });
+
+      var result = await page.evaluate(async function() {
+        return await callController(3, 5);
+      });
+      expect(result).toBe(15);
+    }));
+  });
+
+  describe('Page.setRequestInterceptor', function() {
+    it('should intercept', SX(async function() {
+      page.setRequestInterceptor(request => {
+        expect(request.url()).toContain('empty.html');
+        expect(request.headers()['User-Agent']).toBeTruthy();
+        expect(request.method()).toBe('GET');
+        expect(request.postData()).toBe(undefined);
+        request.continue();
+      });
+      var success = await page.navigate(EMPTY_PAGE);
+      expect(success).toBe(true);
+    }));
+    it('should show extraHTTPHeaders', SX(async function() {
+      await page.setExtraHTTPHeaders({
+        foo: 'bar'
+      });
+      page.setRequestInterceptor(request => {
+        expect(request.headers()['foo']).toBe('bar');
+        request.continue();
+      });
+      var success = await page.navigate(EMPTY_PAGE);
+      expect(success).toBe(true);
+    }));
+    it('should be abortable', SX(async function() {
+      page.setRequestInterceptor(request => {
+        if (request.url().endsWith('.css'))
+          request.abort();
+        else
+          request.continue();
+      });
+      var failedResources = 0;
+      page.on('resourceloadingfailed', event => ++failedResources);
+      var success = await page.navigate(STATIC_PREFIX + '/one-style.html');
+      expect(success).toBe(true);
+      expect(failedResources).toBe(1);
+    }));
+  });
+
+  describe('Page.Events.Dialog', function() {
+    it('should fire', function(done) {
+      page.on('dialog', dialog => {
+        expect(dialog.type).toBe('alert');
+        expect(dialog.message()).toBe('yo');
+        done();
+      });
+      page.evaluate(() => alert('yo'));
     });
+    // TODO Enable this when crbug.com/718235 is fixed.
+    xit('should allow accepting prompts', SX(async function(done) {
+      page.on('dialog', dialog => {
+        expect(dialog.type).toBe('prompt');
+        expect(dialog.message()).toBe('question?');
+        dialog.accept('answer!');
+      });
+      var result = await page.evaluate(() => prompt('question?'));
+      expect(result).toBe('answer!');
+    }));
+  });
 
-    describe('Page.setInPageCallback', function() {
-        it('should work', SX(async function() {
-            await page.setInPageCallback('callController', function(a, b) {
-                return a * b;
-            });
-            var result = await page.evaluate(async function() {
-                return await callController(9, 4);
-            });
-            expect(result).toBe(36);
-        }));
-        it('should survive navigation', SX(async function() {
-            await page.setInPageCallback('callController', function(a, b) {
-                return a * b;
-            });
-
-            await page.navigate(EMPTY_PAGE);
-            var result = await page.evaluate(async function() {
-                return await callController(9, 4);
-            });
-            expect(result).toBe(36);
-        }));
-        it('should await returned promise', SX(async function() {
-            await page.setInPageCallback('callController', function(a, b) {
-                return Promise.resolve(a * b);
-            });
-
-            var result = await page.evaluate(async function() {
-                return await callController(3, 5);
-            });
-            expect(result).toBe(15);
-        }));
+  describe('Page.Events.Error', function() {
+    it('should fire', function(done) {
+      page.on('error', error => {
+        expect(error.message).toContain('Fancy');
+        done();
+      });
+      page.navigate(STATIC_PREFIX + '/error.html');
     });
+  });
 
-    describe('Page.setRequestInterceptor', function() {
-        it('should intercept', SX(async function() {
-            page.setRequestInterceptor(request => {
-                expect(request.url()).toContain('empty.html');
-                expect(request.headers()['User-Agent']).toBeTruthy();
-                expect(request.method()).toBe('GET');
-                expect(request.postData()).toBe(undefined);
-                request.continue();
-            });
-            var success = await page.navigate(EMPTY_PAGE);
-            expect(success).toBe(true);
+  describe('Page.screenshot', function() {
+    it('should work', SX(async function() {
+      await page.setViewportSize({width: 500, height: 500});
+      await page.navigate(STATIC_PREFIX + '/grid.html');
+      var screenshot = await page.screenshot();
+      expect(screenshot).toBeGolden('screenshot-sanity.png');
+    }));
+    it('should clip rect', SX(async function() {
+      await page.setViewportSize({width: 500, height: 500});
+      await page.navigate(STATIC_PREFIX + '/grid.html');
+      var screenshot = await page.screenshot({
+        clip: {
+          x: 50,
+          y: 100,
+          width: 150,
+          height: 100
+        }
+      });
+      expect(screenshot).toBeGolden('screenshot-clip-rect.png');
+    }));
+    it('should work for offscreen clip', SX(async function() {
+      await page.setViewportSize({width: 500, height: 500});
+      await page.navigate(STATIC_PREFIX + '/grid.html');
+      var screenshot = await page.screenshot({
+        clip: {
+          x: 50,
+          y: 600,
+          width: 100,
+          height: 100
+        }
+      });
+      expect(screenshot).toBeGolden('screenshot-offscreen-clip.png');
+    }));
+    it('should run in parallel', SX(async function() {
+      await page.setViewportSize({width: 500, height: 500});
+      await page.navigate(STATIC_PREFIX + '/grid.html');
+      var promises = [];
+      for (var i = 0; i < 3; ++i) {
+        promises.push(page.screenshot({
+          clip: {
+            x: 50 * i,
+            y: 0,
+            width: 50,
+            height: 50
+          }
         }));
-        it('should show extraHTTPHeaders', SX(async function() {
-            await page.setExtraHTTPHeaders({
-                foo: 'bar'
-            });
-            page.setRequestInterceptor(request => {
-                expect(request.headers()['foo']).toBe('bar');
-                request.continue();
-            });
-            var success = await page.navigate(EMPTY_PAGE);
-            expect(success).toBe(true);
-        }));
-        it('should be abortable', SX(async function() {
-            page.setRequestInterceptor(request => {
-                if (request.url().endsWith('.css'))
-                    request.abort();
-                else
-                    request.continue();
-            });
-            var failedResources = 0;
-            page.on('resourceloadingfailed', event => ++failedResources);
-            var success = await page.navigate(STATIC_PREFIX + '/one-style.html');
-            expect(success).toBe(true);
-            expect(failedResources).toBe(1);
-        }));
-    });
+      }
+      var screenshot = await promises[1];
+      expect(screenshot).toBeGolden('screenshot-parallel-calls.png');
+    }));
+    it('should take fullPage screenshots', SX(async function() {
+      await page.setViewportSize({width: 500, height: 500});
+      await page.navigate(STATIC_PREFIX + '/grid.html');
+      var screenshot = await page.screenshot({
+        fullPage: true
+      });
+      expect(screenshot).toBeGolden('screenshot-grid-fullpage.png');
+    }));
+  });
 
-    describe('Page.Events.Dialog', function() {
-        it('should fire', function(done) {
-            page.on('dialog', dialog => {
-                expect(dialog.type).toBe('alert');
-                expect(dialog.message()).toBe('yo');
-                done();
-            });
-            page.evaluate(() => alert('yo'));
-        });
-        // TODO Enable this when crbug.com/718235 is fixed.
-        xit('should allow accepting prompts', SX(async function(done) {
-            page.on('dialog', dialog => {
-                expect(dialog.type).toBe('prompt');
-                expect(dialog.message()).toBe('question?');
-                dialog.accept('answer!');
-            });
-            var result = await page.evaluate(() => prompt('question?'));
-            expect(result).toBe('answer!');
-        }));
-    });
+  describe('Frame Management', function() {
+    var FrameUtils = require('./frame-utils');
+    it('should handle nested frames', SX(async function() {
+      await page.navigate(STATIC_PREFIX + '/frames/nested-frames.html');
+      expect(FrameUtils.dumpFrames(page.mainFrame())).toBeGolden('nested-frames.txt');
+    }));
+    it('should send events when frames are manipulated dynamically', SX(async function() {
+      await page.navigate(EMPTY_PAGE);
+      // validate frameattached events
+      var attachedFrames = [];
+      page.on('frameattached', frame => attachedFrames.push(frame));
+      await FrameUtils.attachFrame(page, 'frame1', './assets/frame.html');
+      expect(attachedFrames.length).toBe(1);
+      expect(attachedFrames[0].url()).toContain('/assets/frame.html');
 
-    describe('Page.Events.Error', function() {
-        it('should fire', function(done) {
-            page.on('error', error => {
-                expect(error.message).toContain('Fancy');
-                done();
-            });
-            page.navigate(STATIC_PREFIX + '/error.html');
-        });
-    });
+      // validate framenavigated events
+      var navigatedFrames = [];
+      page.on('framenavigated', frame => navigatedFrames.push(frame));
+      await FrameUtils.navigateFrame(page, 'frame1', './empty.html');
+      expect(navigatedFrames.length).toBe(1);
+      expect(navigatedFrames[0].url()).toContain('/empty.html');
 
-    describe('Page.screenshot', function() {
-        it('should work', SX(async function() {
-            await page.setViewportSize({width: 500, height: 500});
-            await page.navigate(STATIC_PREFIX + '/grid.html');
-            var screenshot = await page.screenshot();
-            expect(screenshot).toBeGolden('screenshot-sanity.png');
-        }));
-        it('should clip rect', SX(async function() {
-            await page.setViewportSize({width: 500, height: 500});
-            await page.navigate(STATIC_PREFIX + '/grid.html');
-            var screenshot = await page.screenshot({
-                clip: {
-                    x: 50,
-                    y: 100,
-                    width: 150,
-                    height: 100
-                }
-            });
-            expect(screenshot).toBeGolden('screenshot-clip-rect.png');
-        }));
-        it('should work for offscreen clip', SX(async function() {
-            await page.setViewportSize({width: 500, height: 500});
-            await page.navigate(STATIC_PREFIX + '/grid.html');
-            var screenshot = await page.screenshot({
-                clip: {
-                    x: 50,
-                    y: 600,
-                    width: 100,
-                    height: 100
-                }
-            });
-            expect(screenshot).toBeGolden('screenshot-offscreen-clip.png');
-        }));
-        it('should run in parallel', SX(async function() {
-            await page.setViewportSize({width: 500, height: 500});
-            await page.navigate(STATIC_PREFIX + '/grid.html');
-            var promises = [];
-            for (var i = 0; i < 3; ++i) {
-                promises.push(page.screenshot({
-                    clip: {
-                        x: 50 * i,
-                        y: 0,
-                        width: 50,
-                        height: 50
-                    }
-                }));
-            }
-            var screenshot = await promises[1];
-            expect(screenshot).toBeGolden('screenshot-parallel-calls.png');
-        }));
-        it('should take fullPage screenshots', SX(async function() {
-            await page.setViewportSize({width: 500, height: 500});
-            await page.navigate(STATIC_PREFIX + '/grid.html');
-            var screenshot = await page.screenshot({
-                fullPage: true
-            });
-            expect(screenshot).toBeGolden('screenshot-grid-fullpage.png');
-        }));
-    });
+      // validate framedetached events
+      var detachedFrames = [];
+      page.on('framedetached', frame => detachedFrames.push(frame));
+      await FrameUtils.detachFrame(page, 'frame1');
+      expect(detachedFrames.length).toBe(1);
+      expect(detachedFrames[0].isDetached()).toBe(true);
+    }));
+    it('should persist mainFrame on cross-process navigation', SX(async function() {
+      await page.navigate(EMPTY_PAGE);
+      var mainFrame = page.mainFrame();
+      await page.navigate('http://127.0.0.1:' + PORT + '/empty.html');
+      expect(page.mainFrame() === mainFrame).toBeTruthy();
+    }));
+    it('should not send attach/detach events for main frame', SX(async function() {
+      var hasEvents = false;
+      page.on('frameattached', frame => hasEvents = true);
+      page.on('framedetached', frame => hasEvents = true);
+      await page.navigate(EMPTY_PAGE);
+      expect(hasEvents).toBe(false);
+    }));
+    it('should detach child frames on navigation', SX(async function() {
+      var attachedFrames = [];
+      var detachedFrames = [];
+      var navigatedFrames = [];
+      page.on('frameattached', frame => attachedFrames.push(frame));
+      page.on('framedetached', frame => detachedFrames.push(frame));
+      page.on('framenavigated', frame => navigatedFrames.push(frame));
+      await page.navigate(STATIC_PREFIX + '/frames/nested-frames.html');
+      expect(attachedFrames.length).toBe(4);
+      expect(detachedFrames.length).toBe(0);
+      expect(navigatedFrames.length).toBe(5);
 
-    describe('Frame Management', function() {
-        var FrameUtils = require('./frame-utils');
-        it('should handle nested frames', SX(async function() {
-            await page.navigate(STATIC_PREFIX + '/frames/nested-frames.html');
-            expect(FrameUtils.dumpFrames(page.mainFrame())).toBeGolden('nested-frames.txt');
-        }));
-        it('should send events when frames are manipulated dynamically', SX(async function() {
-            await page.navigate(EMPTY_PAGE);
-            // validate frameattached events
-            var attachedFrames = [];
-            page.on('frameattached', frame => attachedFrames.push(frame));
-            await FrameUtils.attachFrame(page, 'frame1', './assets/frame.html');
-            expect(attachedFrames.length).toBe(1);
-            expect(attachedFrames[0].url()).toContain('/assets/frame.html');
-
-            // validate framenavigated events
-            var navigatedFrames = [];
-            page.on('framenavigated', frame => navigatedFrames.push(frame));
-            await FrameUtils.navigateFrame(page, 'frame1', './empty.html');
-            expect(navigatedFrames.length).toBe(1);
-            expect(navigatedFrames[0].url()).toContain('/empty.html');
-
-            // validate framedetached events
-            var detachedFrames = [];
-            page.on('framedetached', frame => detachedFrames.push(frame));
-            await FrameUtils.detachFrame(page, 'frame1');
-            expect(detachedFrames.length).toBe(1);
-            expect(detachedFrames[0].isDetached()).toBe(true);
-        }));
-        it('should persist mainFrame on cross-process navigation', SX(async function() {
-            await page.navigate(EMPTY_PAGE);
-            var mainFrame = page.mainFrame();
-            await page.navigate('http://127.0.0.1:' + PORT + '/empty.html');
-            expect(page.mainFrame() === mainFrame).toBeTruthy();
-        }));
-        it('should not send attach/detach events for main frame', SX(async function() {
-            var hasEvents = false;
-            page.on('frameattached', frame => hasEvents = true);
-            page.on('framedetached', frame => hasEvents = true);
-            await page.navigate(EMPTY_PAGE);
-            expect(hasEvents).toBe(false);
-        }));
-        it('should detach child frames on navigation', SX(async function() {
-            var attachedFrames = [];
-            var detachedFrames = [];
-            var navigatedFrames = [];
-            page.on('frameattached', frame => attachedFrames.push(frame));
-            page.on('framedetached', frame => detachedFrames.push(frame));
-            page.on('framenavigated', frame => navigatedFrames.push(frame));
-            await page.navigate(STATIC_PREFIX + '/frames/nested-frames.html');
-            expect(attachedFrames.length).toBe(4);
-            expect(detachedFrames.length).toBe(0);
-            expect(navigatedFrames.length).toBe(5);
-
-            var attachedFrames = [];
-            var detachedFrames = [];
-            var navigatedFrames = [];
-            await page.navigate(EMPTY_PAGE);
-            expect(attachedFrames.length).toBe(0);
-            expect(detachedFrames.length).toBe(4);
-            expect(navigatedFrames.length).toBe(1);
-        }));
-    });
+      var attachedFrames = [];
+      var detachedFrames = [];
+      var navigatedFrames = [];
+      await page.navigate(EMPTY_PAGE);
+      expect(attachedFrames.length).toBe(0);
+      expect(detachedFrames.length).toBe(4);
+      expect(navigatedFrames.length).toBe(1);
+    }));
+  });
 });
 
 // Since Jasmine doesn't like async functions, they should be wrapped
 // in a SX function.
 function SX(fun) {
-    return done => Promise.resolve(fun()).then(done).catch(done.fail);
+  return done => Promise.resolve(fun()).then(done).catch(done.fail);
 }
diff --git a/utils/ChromiumDownloader.js b/utils/ChromiumDownloader.js
index 5b5510b220a..5d868ec92a1 100644
--- a/utils/ChromiumDownloader.js
+++ b/utils/ChromiumDownloader.js
@@ -25,107 +25,107 @@ var URL = require('url');
 var CHROMIUM_PATH = path.join(__dirname, '..', '.local-chromium');
 
 var downloadURLs = {
-    linux: 'https://storage.googleapis.com/chromium-browser-snapshots/Linux_x64/%d/chrome-linux.zip',
-    mac: 'https://storage.googleapis.com/chromium-browser-snapshots/Mac/%d/chrome-mac.zip',
-    win32: 'https://storage.googleapis.com/chromium-browser-snapshots/Win/%d/chrome-win32.zip',
-    win64: 'https://storage.googleapis.com/chromium-browser-snapshots/Win_x64/%d/chrome-win32.zip',
+  linux: 'https://storage.googleapis.com/chromium-browser-snapshots/Linux_x64/%d/chrome-linux.zip',
+  mac: 'https://storage.googleapis.com/chromium-browser-snapshots/Mac/%d/chrome-mac.zip',
+  win32: 'https://storage.googleapis.com/chromium-browser-snapshots/Win/%d/chrome-win32.zip',
+  win64: 'https://storage.googleapis.com/chromium-browser-snapshots/Win_x64/%d/chrome-win32.zip',
 };
 
 module.exports = {
-    /**
-     * @return {!Array<string>}
-     */
-    supportedPlatforms: function() {
-        return Object.keys(downloadURLs);
-    },
+  /**
+   * @return {!Array<string>}
+   */
+  supportedPlatforms: function() {
+    return Object.keys(downloadURLs);
+  },
 
-    /**
-     * @return {string}
-     */
-    currentPlatform: function() {
-        var platform = os.platform();
-        if (platform === 'darwin')
-            return 'mac';
-        if (platform === 'linux')
-            return 'linux';
-        if (platform === 'win32')
-            return os.arch() === 'x64' ? 'win64' : 'win32';
-        return '';
-    },
+  /**
+   * @return {string}
+   */
+  currentPlatform: function() {
+    var platform = os.platform();
+    if (platform === 'darwin')
+      return 'mac';
+    if (platform === 'linux')
+      return 'linux';
+    if (platform === 'win32')
+      return os.arch() === 'x64' ? 'win64' : 'win32';
+    return '';
+  },
 
-    /**
-     * @param {string} platform
-     * @param {string} revision
-     * @return {!Promise<boolean>}
-     */
-    canDownloadRevision: function(platform, revision) {
-        console.assert(downloadURLs[platform], 'Unknown platform: ' + platform);
-        var url = URL.parse(util.format(downloadURLs[platform], revision));
-        var options = {
-            method: 'HEAD',
-            host: url.host,
-            path: url.pathname,
-        };
-        var resolve;
-        var promise = new Promise(x => resolve = x);
-        var request = https.request(options, response => {
-            resolve(response.statusCode === 200);
-        });
-        request.on('error', error => {
-            console.error(error);
-            resolve(false);
-        });
-        request.end();
-        return promise;
-    },
+  /**
+   * @param {string} platform
+   * @param {string} revision
+   * @return {!Promise<boolean>}
+   */
+  canDownloadRevision: function(platform, revision) {
+    console.assert(downloadURLs[platform], 'Unknown platform: ' + platform);
+    var url = URL.parse(util.format(downloadURLs[platform], revision));
+    var options = {
+      method: 'HEAD',
+      host: url.host,
+      path: url.pathname,
+    };
+    var resolve;
+    var promise = new Promise(x => resolve = x);
+    var request = https.request(options, response => {
+      resolve(response.statusCode === 200);
+    });
+    request.on('error', error => {
+      console.error(error);
+      resolve(false);
+    });
+    request.end();
+    return promise;
+  },
 
-    /**
-     * @param {string} platform
-     * @param {string} revision
-     * @param {?function(number, number)} progressCallback
-     * @return {!Promise}
-     */
-    downloadRevision: async function(platform, revision, progressCallback) {
-        var url = downloadURLs[platform];
-        console.assert(url, `Unsupported platform: ${platform}`);
-        url = util.format(url, revision);
-        var zipPath = path.join(CHROMIUM_PATH, `download-${platform}-${revision}.zip`);
-        var folderPath = getFolderPath(platform, revision);
-        if (fs.existsSync(folderPath))
-            return;
-        try {
-            if (!fs.existsSync(CHROMIUM_PATH))
-                fs.mkdirSync(CHROMIUM_PATH);
-            await downloadFile(url, zipPath, progressCallback);
-            await extractZip(zipPath, folderPath);
-        } finally {
-            if (fs.existsSync(zipPath))
-                fs.unlinkSync(zipPath);
-        }
-    },
+  /**
+   * @param {string} platform
+   * @param {string} revision
+   * @param {?function(number, number)} progressCallback
+   * @return {!Promise}
+   */
+  downloadRevision: async function(platform, revision, progressCallback) {
+    var url = downloadURLs[platform];
+    console.assert(url, `Unsupported platform: ${platform}`);
+    url = util.format(url, revision);
+    var zipPath = path.join(CHROMIUM_PATH, `download-${platform}-${revision}.zip`);
+    var folderPath = getFolderPath(platform, revision);
+    if (fs.existsSync(folderPath))
+      return;
+    try {
+      if (!fs.existsSync(CHROMIUM_PATH))
+        fs.mkdirSync(CHROMIUM_PATH);
+      await downloadFile(url, zipPath, progressCallback);
+      await extractZip(zipPath, folderPath);
+    } finally {
+      if (fs.existsSync(zipPath))
+        fs.unlinkSync(zipPath);
+    }
+  },
 
-    /**
-     * @param {string} platform
-     * @param {string} revision
-     * @return {?{executablePath: string}}
-     */
-    revisionInfo: function(platform, revision) {
-        var folderPath = getFolderPath(platform, revision);
-        if (!fs.existsSync(folderPath))
-            return null;
-        var executablePath = '';
-        if (platform === 'mac')
-            executablePath = path.join(folderPath, 'chrome-mac', 'Chromium.app', 'Contents', 'MacOS', 'Chromium');
-        else if (platform === 'linux')
-            executablePath = path.join(folderPath, 'chrome-linux', 'chrome');
-        else if (platform === 'win32' || platform === 'win64')
-            executablePath = path.join(folderPath, 'chrome-win32', 'chrome.exe');
-        else
-            throw 'Unsupported platfrom: ' + platfrom;
-        return {
-            executablePath: executablePath
-        };
-    },
+  /**
+   * @param {string} platform
+   * @param {string} revision
+   * @return {?{executablePath: string}}
+   */
+  revisionInfo: function(platform, revision) {
+    var folderPath = getFolderPath(platform, revision);
+    if (!fs.existsSync(folderPath))
+      return null;
+    var executablePath = '';
+    if (platform === 'mac')
+      executablePath = path.join(folderPath, 'chrome-mac', 'Chromium.app', 'Contents', 'MacOS', 'Chromium');
+    else if (platform === 'linux')
+      executablePath = path.join(folderPath, 'chrome-linux', 'chrome');
+    else if (platform === 'win32' || platform === 'win64')
+      executablePath = path.join(folderPath, 'chrome-win32', 'chrome.exe');
+    else
+      throw 'Unsupported platfrom: ' + platfrom;
+    return {
+      executablePath: executablePath
+    };
+  },
 };
 
 /**
@@ -134,7 +134,7 @@ module.exports = {
  * @return {string}
  */
 function getFolderPath(platform, revision) {
-    return path.join(CHROMIUM_PATH, platform + '-' + revision);
+  return path.join(CHROMIUM_PATH, platform + '-' + revision);
 }
 
 /**
@@ -144,30 +144,30 @@ function getFolderPath(platform, revision) {
  * @return {!Promise}
  */
 function downloadFile(url, destinationPath, progressCallback) {
-    var fulfill, reject;
-    var promise = new Promise((x, y) => { fulfill = x; reject = y; });
-    var request = https.get(url, response => {
-        if (response.statusCode !== 200) {
-            var error = new Error(`Download failed: server returned code ${response.statusCode}. URL: ${url}`);
-            // consume response data to free up memory
-            response.resume();
-            reject(error);
-            return;
-        }
-        var file = fs.createWriteStream(destinationPath);
-        file.on('finish', () => fulfill());
-        file.on('error', error => reject(error));
-        response.pipe(file);
-        var totalBytes = parseInt(response.headers['content-length'], 10);
-        if (progressCallback)
-            response.on('data', onData.bind(null, totalBytes));
-    });
-    request.on('error', error => reject(error));
-    return promise;
-
-    function onData(totalBytes, chunk) {
-        progressCallback(totalBytes, chunk.length);
+  var fulfill, reject;
+  var promise = new Promise((x, y) => { fulfill = x; reject = y; });
+  var request = https.get(url, response => {
+    if (response.statusCode !== 200) {
+      var error = new Error(`Download failed: server returned code ${response.statusCode}. URL: ${url}`);
+      // consume response data to free up memory
+      response.resume();
+      reject(error);
+      return;
     }
+    var file = fs.createWriteStream(destinationPath);
+    file.on('finish', () => fulfill());
+    file.on('error', error => reject(error));
+    response.pipe(file);
+    var totalBytes = parseInt(response.headers['content-length'], 10);
+    if (progressCallback)
+      response.on('data', onData.bind(null, totalBytes));
+  });
+  request.on('error', error => reject(error));
+  return promise;
+
+  function onData(totalBytes, chunk) {
+    progressCallback(totalBytes, chunk.length);
+  }
 }
 
 /**
@@ -176,5 +176,5 @@ function downloadFile(url, destinationPath, progressCallback) {
  * @return {!Promise<?Error>}
  */
 function extractZip(zipPath, folderPath) {
-    return new Promise(fulfill => extract(zipPath, {dir: folderPath}, fulfill));
+  return new Promise(fulfill => extract(zipPath, {dir: folderPath}, fulfill));
 }
diff --git a/utils/check_availability.js b/utils/check_availability.js
index 8a3501beec3..7b083820fac 100755
--- a/utils/check_availability.js
+++ b/utils/check_availability.js
@@ -20,43 +20,43 @@ var https = require('https');
 var OMAHA_PROXY = 'https://omahaproxy.appspot.com/all.json';
 
 var colors = {
-    reset: '\x1b[0m',
-    red: '\x1b[31m',
-    green: '\x1b[32m',
-    yellow: '\x1b[33m'
+  reset: '\x1b[0m',
+  red: '\x1b[31m',
+  green: '\x1b[32m',
+  yellow: '\x1b[33m'
 };
 
 class Table {
-    /**
-     * @param {!Array<number>} columnWidths
-     */
-    constructor(columnWidths) {
-        this.widths = columnWidths;
-    }
+  /**
+   * @param {!Array<number>} columnWidths
+   */
+  constructor(columnWidths) {
+    this.widths = columnWidths;
+  }
 
-    /**
-     * @param {!Array<string>} values
-     */
-    drawRow(values) {
-        console.assert(values.length === this.widths.length);
-        var row = '';
-        for (var i = 0; i < values.length; ++i)
-            row += padCenter(values[i], this.widths[i]);
-        console.log(row);
-    }
+  /**
+   * @param {!Array<string>} values
+   */
+  drawRow(values) {
+    console.assert(values.length === this.widths.length);
+    var row = '';
+    for (var i = 0; i < values.length; ++i)
+      row += padCenter(values[i], this.widths[i]);
+    console.log(row);
+  }
 }
 
 if (process.argv.length === 2) {
-    checkOmahaProxyAvailability();
-    return;
+  checkOmahaProxyAvailability();
+  return;
 }
 if (process.argv.length !== 4) {
-    console.log(`
+  console.log(`
   Usage: node check_revisions.js [fromRevision] [toRevision]
 
 This script checks availability of different prebuild chromium revisions.
 Running command without arguments will check against omahaproxy revisions.`);
-    return;
+  return;
 }
 
 var fromRevision = parseInt(process.argv[2], 10);
@@ -67,27 +67,27 @@ checkRangeAvailability(fromRevision, toRevision);
  * @return {!Promise}
  */
 async function checkOmahaProxyAvailability() {
-    console.log('Fetching revisions from ' + OMAHA_PROXY);
-    var platforms = await loadJSON(OMAHA_PROXY);
-    if (!platforms) {
-        console.error('ERROR: failed to fetch chromium revisions from omahaproxy.');
-        return;
-    }
-    var table = new Table([27, 7, 7, 7, 7]);
-    table.drawRow([''].concat(Downloader.supportedPlatforms()));
-    for (var platform of platforms) {
-        // Trust only to the main platforms.
-        if (platform.os !== 'mac' && platform.os !== 'win' && platform.os !== 'win64' && platform.os !== 'linux')
-            continue;
-        var osName = platform.os === 'win' ? 'win32' : platform.os;
-        for (var version of platform.versions) {
-            if (version.channel !== 'dev' && version.channel !== 'beta' && version.channel !== 'canary' && version.channel !== 'stable')
-                continue;
-            var revisionName = padLeft('[' + osName + ' ' + version.channel + ']', 15);
-            var revision = parseInt(version.branch_base_position, 10);
-            await checkAndDrawRevisionAvailability(table, revisionName, revision);
-        }
+  console.log('Fetching revisions from ' + OMAHA_PROXY);
+  var platforms = await loadJSON(OMAHA_PROXY);
+  if (!platforms) {
+    console.error('ERROR: failed to fetch chromium revisions from omahaproxy.');
+    return;
+  }
+  var table = new Table([27, 7, 7, 7, 7]);
+  table.drawRow([''].concat(Downloader.supportedPlatforms()));
+  for (var platform of platforms) {
+    // Trust only to the main platforms.
+    if (platform.os !== 'mac' && platform.os !== 'win' && platform.os !== 'win64' && platform.os !== 'linux')
+      continue;
+    var osName = platform.os === 'win' ? 'win32' : platform.os;
+    for (var version of platform.versions) {
+      if (version.channel !== 'dev' && version.channel !== 'beta' && version.channel !== 'canary' && version.channel !== 'stable')
+        continue;
+      var revisionName = padLeft('[' + osName + ' ' + version.channel + ']', 15);
+      var revision = parseInt(version.branch_base_position, 10);
+      await checkAndDrawRevisionAvailability(table, revisionName, revision);
     }
+  }
 }
 
 /**
@@ -96,11 +96,11 @@ async function checkOmahaProxyAvailability() {
  * @return {!Promise}
  */
 async function checkRangeAvailability(fromRevision, toRevision) {
-    var table = new Table([10, 7, 7, 7, 7]);
-    table.drawRow([''].concat(Downloader.supportedPlatforms()));
-    var inc = fromRevision < toRevision ? 1 : -1;
-    for (var revision = fromRevision; revision !== toRevision; revision += inc)
-        await checkAndDrawRevisionAvailability(table, '', revision);
+  var table = new Table([10, 7, 7, 7, 7]);
+  table.drawRow([''].concat(Downloader.supportedPlatforms()));
+  var inc = fromRevision < toRevision ? 1 : -1;
+  for (var revision = fromRevision; revision !== toRevision; revision += inc)
+    await checkAndDrawRevisionAvailability(table, '', revision);
 }
 
 /**
@@ -110,18 +110,18 @@ async function checkRangeAvailability(fromRevision, toRevision) {
  * @return {!Promise}
  */
 async function checkAndDrawRevisionAvailability(table, name, revision) {
-    var promises = [];
-    for (var platform of Downloader.supportedPlatforms())
-        promises.push(Downloader.canDownloadRevision(platform, revision));
-    var availability = await Promise.all(promises);
-    var allAvailable = availability.every(e => !!e);
-    var values = [name + ' ' + (allAvailable ? colors.green + revision + colors.reset : revision)];
-    for (var i = 0; i < availability.length; ++i) {
-        var decoration = availability[i] ? '+' : '-';
-        var color = availability[i] ? colors.green : colors.red;
-        values.push(color + decoration + colors.reset);
-    }
-    table.drawRow(values);
+  var promises = [];
+  for (var platform of Downloader.supportedPlatforms())
+    promises.push(Downloader.canDownloadRevision(platform, revision));
+  var availability = await Promise.all(promises);
+  var allAvailable = availability.every(e => !!e);
+  var values = [name + ' ' + (allAvailable ? colors.green + revision + colors.reset : revision)];
+  for (var i = 0; i < availability.length; ++i) {
+    var decoration = availability[i] ? '+' : '-';
+    var color = availability[i] ? colors.green : colors.red;
+    values.push(color + decoration + colors.reset);
+  }
+  table.drawRow(values);
 }
 
 /**
@@ -129,26 +129,26 @@ async function checkAndDrawRevisionAvailability(table, name, revision) {
  * @return {!Promise<?Object>}
  */
 function loadJSON(url) {
-    var resolve;
-    var promise = new Promise(x => resolve = x);
-    https.get(url, response => {
-        if (response.statusCode !== 200) {
-            resolve(null);
-            return;
-        }
-        var body = '';
-        response.on('data', function(chunk){
-            body += chunk;
-        });
-        response.on('end', function(){
-            var json = JSON.parse(body);
-            resolve(json);
-        });
-    }).on('error', function(e){
-          console.error('Error fetching json: ' + e);
-          resolve(null);
+  var resolve;
+  var promise = new Promise(x => resolve = x);
+  https.get(url, response => {
+    if (response.statusCode !== 200) {
+      resolve(null);
+      return;
+    }
+    var body = '';
+    response.on('data', function(chunk){
+      body += chunk;
     });
-    return promise;
+    response.on('end', function(){
+      var json = JSON.parse(body);
+      resolve(json);
+    });
+  }).on('error', function(e){
+    console.error('Error fetching json: ' + e);
+    resolve(null);
+  });
+  return promise;
 }
 
 /**
@@ -156,7 +156,7 @@ function loadJSON(url) {
  * @return {string}
  */
 function spaceString(size) {
-    return new Array(size).fill(' ').join('');
+  return new Array(size).fill(' ').join('');
 }
 
 /**
@@ -164,11 +164,11 @@ function spaceString(size) {
  * @return {string}
  */
 function filterOutColors(text) {
-    for (var colorName in colors) {
-        var color = colors[colorName];
-        text = text.replace(color, '');
-    }
-    return text;
+  for (var colorName in colors) {
+    var color = colors[colorName];
+    text = text.replace(color, '');
+  }
+  return text;
 }
 
 /**
@@ -177,8 +177,8 @@ function filterOutColors(text) {
  * @return {string}
  */
 function padLeft(text, length) {
-    var printableCharacters = filterOutColors(text);
-    return printableCharacters.length >= length ? text : spaceString(length - text.length) + text;
+  var printableCharacters = filterOutColors(text);
+  return printableCharacters.length >= length ? text : spaceString(length - text.length) + text;
 }
 
 /**
@@ -187,10 +187,10 @@ function padLeft(text, length) {
  * @return {string}
  */
 function padCenter(text, length) {
-    var printableCharacters = filterOutColors(text);
-    if (printableCharacters.length >= length)
-        return text;
-    var left = Math.floor((length - printableCharacters.length) / 2);
-    var right = Math.ceil((length - printableCharacters.length) / 2);
-    return spaceString(left) + text + spaceString(right);
+  var printableCharacters = filterOutColors(text);
+  if (printableCharacters.length >= length)
+    return text;
+  var left = Math.floor((length - printableCharacters.length) / 2);
+  var right = Math.ceil((length - printableCharacters.length) / 2);
+  return spaceString(left) + text + spaceString(right);
 }
diff --git a/yarn.lock b/yarn.lock
index 9e03dc6eb1f..588bbae10d0 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -753,6 +753,10 @@ table@^4.0.1:
     slice-ansi "0.0.4"
     string-width "^2.0.0"
 
+text-diff@^1.0.1:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/text-diff/-/text-diff-1.0.1.tgz#6c105905435e337857375c9d2f6ca63e453ff565"
+
 text-table@~0.2.0:
   version "0.2.0"
   resolved "https://registry.yarnpkg.com/text-table/-/text-table-0.2.0.tgz#7f5ee823ae805207c00af2df4a84ec3fcfa570b4"