GitLab

* Handling RenderProcessGone in CastWindowAndroid
* Using CastBrowserProcess instead of passing the browser context
* A few style nits

R=byungchul@chromium.org,lcwu@chromium.org
BUG=None

Review URL: https://codereview.chromium.org/566963003

Cr-Commit-Position: refs/heads/master@{#295210}