This sets up API to release OutputSurface from LTHClient.
It will be helpful in Android where we can release OutputSurface without
destroying LTHClient, thereby making OutputSurface switches have less glitches.

BUG=374906
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel

Review URL: https://codereview.chromium.org/1287043002

Cr-Commit-Position: refs/heads/master@{#349787}
12 files changed