This CL adds methods to manipulate RTP header extension, particularly
AbsoulteSendTime extension. If there is matching extension ID present
in RTP packet, we will update with the current time.

R=solenberg@chromium.org, juberti@chromium.org, sergeyu@chromium.org

BUG=

Review URL: https://codereview.chromium.org/159353002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@256580 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 256580
chromeos: Remove old LockScreen signal.

Remove code that listened for a LockScreen D-Bus signal,
formerly emitted by the session manager to instruct Chrome
to lock the screen. Chrome now exports a LockScreen method
instead.

BUG=341921

Review URL: https://codereview.chromium.org/167663004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@256581 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 256581