Add new PPB_OPENGLES2_DRAWBUFFERS_DEV_INTERFACE_1_0 pepper interface.

This allows applications to draw to multiple render targets at the same time.

BUG=318019

Review URL: https://codereview.chromium.org/182213003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@255222 0039d316-1c4b-4281-b951-d872f2087c98
Add rdevlin.cronin@ to OWNERS for extensions

NOTRY=true

Review URL: https://codereview.chromium.org/183793009

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@255223 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 255222
[Android] Additional events to observe in TabObserver.

BUG=344589,341231
TEST=none
NOTRY=True

Review URL: https://codereview.chromium.org/181063034

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@255224 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 255224