cc: Tear down frame sink when worker context is lost.

Worker context is on a different share group from compositor context so
worker context lost notification does not propagate to compositor context.
This is mostly fine because we restart the gpu process anyway but we don't
for synthetic context loss such as out of memory conditions.

R=piman,danakj
BUG=786570

Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel;master.tryserver.chromium.android:android_optional_gpu_tests_rel
Change-Id: I4afda056ba7399806c9dd56d83a2efb208c95847
Reviewed-on: https://chromium-review.googlesource.com/795184
Commit-Queue: Sunny Sachanandani <[email protected]>
Reviewed-by: Bo <[email protected]>
Reviewed-by: Sadrul Chowdhury <[email protected]>
Reviewed-by: danakj <[email protected]>
Reviewed-by: Antoine Labour <[email protected]>
Cr-Commit-Position: refs/heads/master@{#523513}
26 files changed