Add switch enable-linkable-ephemeral-apps

Added switch "enable-linkable-ephemeral-apps" for experimentation with launching
ephemeral apps from hyperlinks. This functionality was previously behind
the "enable-ephemeral-apps" switch, but the two features will now be
separated.

This patch also ensures that only links appearing on a Google search
result page will launch the app.

Ephemeral apps are now enabled for Windows, Linux and ChromeOS platforms.

BUG=312460

Review URL: https://codereview.chromium.org/90783002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@237722 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 237722
Linux: init_process_reaper comment cleanup.

Cleanup a few comments in init_process_reaper.cc

BUG=312380

Review URL: https://codereview.chromium.org/92963002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@237723 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 237723
Roll ANGLE DEPS to include new device removed change.

BUG=

Review URL: https://codereview.chromium.org/92403002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@237724 0039d316-1c4b-4281-b951-d872f2087c98
Update .DEPS.git

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@237725 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 237725