[android] Make RWHVAndroid a BeginFrameObserver.

content/browser/android/synchronous_compositor_browser_filter.cc

Index: content/browser/android/synchronous_compositor_browser_filter.cc
diff --git a/content/browser/android/synchronous_compositor_browser_filter.cc b/content/browser/android/synchronous_compositor_browser_filter.cc
index 6775f04c8793acf9ae931be262a58ec61aa10d96..4c063a2c70253e57cba75e564c5572634a90c665 100644
--- a/content/browser/android/synchronous_compositor_browser_filter.cc
+++ b/content/browser/android/synchronous_compositor_browser_filter.cc
@@ -45,7 +45,7 @@ void SynchronousCompositorBrowserFilter::SyncStateAfterVSync(
   if (window_android_in_vsync_)
     return;
   window_android_in_vsync_ = window_android;
-  window_android_in_vsync_->AddObserver(this);
+  window_android_in_vsync_->GetBeginFrameSource()->AddObserver(this);
 }
 
 bool SynchronousCompositorBrowserFilter::OnMessageReceived(
@@ -177,30 +177,13 @@ void SynchronousCompositorBrowserFilter::SignalAllFutures() {
   filter_ready_ = false;
 }
 
-void SynchronousCompositorBrowserFilter::OnCompositingDidCommit() {
-  NOTREACHED();
-}
-
-void SynchronousCompositorBrowserFilter::OnRootWindowVisibilityChanged(
-    bool visible) {
-  NOTREACHED();
-}
-
-void SynchronousCompositorBrowserFilter::OnAttachCompositor() {
-  NOTREACHED();
-}
-
-void SynchronousCompositorBrowserFilter::OnDetachCompositor() {
-  NOTREACHED();
-}
-
-void SynchronousCompositorBrowserFilter::OnVSync(base::TimeTicks frame_time,
-                                                 base::TimeDelta vsync_period) {
-  // This is called after DidSendBeginFrame for SynchronousCompositorHosts
+void SynchronousCompositorBrowserFilter::OnBeginFrame(
+    const cc::BeginFrameArgs& args) {
+  // This is called after DidSendBeginFrame for all SynchronousCompositorHosts
   // belonging to this WindowAndroid, since this is added as an Observer after
   // the observer iteration has started.
   DCHECK(window_android_in_vsync_);
-  window_android_in_vsync_->RemoveObserver(this);
+  window_android_in_vsync_->GetBeginFrameSource()->RemoveObserver(this);
   window_android_in_vsync_ = nullptr;
 
   std::vector<int> routing_ids;
@@ -229,12 +212,19 @@ void SynchronousCompositorBrowserFilter::OnVSync(base::TimeTicks frame_time,
   compositor_host_pending_renderer_state_.clear();
 }
 
-void SynchronousCompositorBrowserFilter::OnActivityStopped() {
+const cc::BeginFrameArgs&
+SynchronousCompositorBrowserFilter::LastUsedBeginFrameArgs() const {
+  // Not called by the source since we add and remove ourselves during a single
+  // OnVSync() iteration.
   NOTREACHED();
+  static cc::BeginFrameArgs args;

[boliu, 2016/12/12 21:41:48]

static is overkill

[Eric Seckler, 2016/12/13 10:03:55]

hmm, this returns a reference - don't think I can return a reference to a local
var without the compiler complaining?

[boliu, 2016/12/13 18:07:47]

Doh, yeah, ok.

But then I think this causes a static initializer, which is supposed to be
banned (I'm not sure if there are bots on android that checks this though)

Just use a member variable

[Eric Seckler, 2016/12/14 15:36:57]

Don't think it would cause a static initializer - static in function scope
should be initialized at first invocation. Anyway, replaced by a member variable
since this seems to be irritating :)

+  return args;
 }
 
-void SynchronousCompositorBrowserFilter::OnActivityStarted() {
-  NOTREACHED();
+void SynchronousCompositorBrowserFilter::OnBeginFrameSourcePausedChanged(
+    bool paused) {
+  // The BeginFrameSources we listen to don't use this.
+  DCHECK(!paused);
 }
 
 }  // namespace content