GitLab

Explicitly notify the FrameSequenceTracker instances when handling a
frame terminates. This is used to validate that the expected sequence
of calls happen correctly, e.g. a new frame does not start before the
earlier frame has completely been processed.

BUG=1021963

Change-Id: I9465148c7478545723e2b3657fdd9b49cdc79d3d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1902069
Commit-Queue: Sadrul Chowdhury <sadrul@chromium.org>
Reviewed-by: Robert Flack <flackr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#723652}