This patch removes all dynamic requires in Puppeteer. This should
make it much simpler to bundle puppeteer/puppeteer-core packages.
We used dynamic requires in a few places in lib/:
- BrowserFetcher was choosing between `http` and `https` based on some
runtime value. This was easy to fix with explicit `require`.
- BrowserFetcher and Launcher needed to know project root to store
chromium revisions and to read package name and chromium revision from
package.json. (projectRoot value would be different in node6).
Instead of doing a backwards logic to infer these
variables, we now pass them directly from `//index.js`.
With this patch, I was able to bundle Puppeteer using browserify and
the following config in `package.json`:
```json
"browser": {
"./lib/BrowserFetcher.js": false,
"ws": "./lib/BrowserWebSocket",
"fs": false,
"child_process": false,
"rimraf": false,
"readline": false
}
```
(where `lib/BrowserWebSocket.js` is a courtesy of @Janpot from
https://github.com/GoogleChrome/puppeteer/pull/2374/)
And command:
```sh
$ browserify -r puppeteer:./index.js > ppweb.js
```
References #2119
f230722ff0