chore: use unique version for puppeteer@next (#1688)

This patch starts amending package.json with a unique puppeteer@next version
so that it gets published on npm.

.travis.yml

@@ -27,6 +27,7 @@ jobs:
       env: NODE7=true
     - node_js: "6.4.0"
       env: NODE6=true
+before_deploy: "yarn run apply-next-version"
 deploy:
   provider: npm
   email: aslushnikov@gmail.com

package.json

@@ -20,7 +20,8 @@
     "build": "node utils/node6-transform/index.js",
     "unit-node6": "node node6/test/test.js",
     "tsc": "tsc -p .",
-    "prepublishOnly": "npm run build"
+    "prepublishOnly": "npm run build",
+    "apply-next-version": "node utils/apply_next_version.js"
   },
   "author": "The Chromium Authors",
   "license": "Apache-2.0",

utils/apply_next_version.js

@@ -0,0 +1,12 @@
+const path = require('path');
+const fs = require('fs');
+
+const package = require('../package.json');
+let version = package.version;
+const dashIndex = version.indexOf('-');
+if (dashIndex !== -1)
+  version = version.substring(0, dashIndex);
+version += '-next.' + Date.now();
+console.log('Setting version to ' + version);
+package.version = version;
+fs.writeFileSync(path.join(__dirname, '..', 'package.json'), JSON.stringify(package, undefined, 2) + '\n');