GitLab

Instead of directly observing the Window's vsyncs, RWHVAndroid now
observes a BeginFrameSource provided by the DelegatedFrameHost (clank)
or WindowAndroid (webview). To enable this, the BeginFrameSource
originally provided by CompositorImpl moves into WindowAndroid.

The patch also makes some changes to the BeginFrameSource's observer
iteration that are necessary to support
SynchronousBrowserCompositorFilter.

BUG=401336, 675289

Committed: https://crrev.com/1a6bd5037fc10e45646715d675e63146d23fc28d
Review-Url: https://codereview.chromium.org/2564403002
Cr-Original-Commit-Position: refs/heads/master@{#439072}
Cr-Commit-Position: refs/heads/master@{#439877}