GitLab

Set up a counter in LayerTreeImpl to indicate whether a recent frame has
been pushed from main thread. Since missing and incomplete tiles are
compositor side concept, only track those numbers on compositor side.

BUG=381695

Review URL: https://codereview.chromium.org/411693004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@285010 0039d316-1c4b-4281-b951-d872f2087c98