cc: Poll for state that triggers draws (synchronous compositor only)
commit02de8f45bf1a1fd1760a3fa3dbc12c106f0cbe05
authorbrianderson@chromium.org <brianderson@chromium.org@0039d316-1c4b-4281-b951-d872f2087c98>
Thu, 12 Sep 2013 05:27:52 +0000 (12 05:27 +0000)
committerbrianderson@chromium.org <brianderson@chromium.org@0039d316-1c4b-4281-b951-d872f2087c98>
Thu, 12 Sep 2013 05:27:52 +0000 (12 05:27 +0000)
treef2210c0bcd0a627012173d711d89b5e7ccf0cf3c
parent5582b8a2b33ff099a2cee62a5abb92865c330189
cc: Poll for state that triggers draws (synchronous compositor only)

This adds Scheduler::PollForAnticipatedDrawTriggers which is used
by the synchronous compositor to avoid requesting BeginImplFrames
when we might not actually draw new content, but still need to
monitor state that might trigger a draw at vsync intervals.

This can occur, for example, when the last swap used incomplete tiles
(checkerboards or low-quality) or when a commit is aborted and we
want to wait a vsync before starting the next commit.

BUG=284810

Review URL: https://chromiumcodereview.appspot.com/23463014

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@222711 0039d316-1c4b-4281-b951-d872f2087c98
cc/scheduler/scheduler.cc
cc/scheduler/scheduler.h
cc/scheduler/scheduler_state_machine.cc
cc/scheduler/scheduler_state_machine.h
cc/trees/layer_tree_host_unittest.cc