Use to base::checked_cast.

Review URL: https://codereview.chromium.org/171683020

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252753 0039d316-1c4b-4281-b951-d872f2087c98
Changed tags to match caps printers.

Review URL: https://codereview.chromium.org/174433003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252754 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 252753
[PPAPI][MediaStream] Add browser tests for MediaStreamAudioTrack

BUG=330851

Review URL: https://codereview.chromium.org/175383003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252755 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 252754
Add end to end test for Media galleries scan API.

BUG=161119

Review URL: https://codereview.chromium.org/174013009

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252756 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 252755
SVN changes up to revision 252756