cc: Make scheduling be driven by vsync for android webview.

content/browser/android/in_process/synchronous_compositor_external_begin_frame_source.cc

Index: content/browser/android/in_process/synchronous_compositor_external_begin_frame_source.cc
diff --git a/content/browser/android/in_process/synchronous_compositor_external_begin_frame_source.cc b/content/browser/android/in_process/synchronous_compositor_external_begin_frame_source.cc
index 0c272fd358af42ff8789ad2ba672d74ed55d49b4..bf871cf49e214490c8592b82b397ed647456cb43 100644
--- a/content/browser/android/in_process/synchronous_compositor_external_begin_frame_source.cc
+++ b/content/browser/android/in_process/synchronous_compositor_external_begin_frame_source.cc
@@ -30,11 +30,19 @@ SynchronousCompositorExternalBeginFrameSource::
   DCHECK(!compositor_);
 }
 
-void SynchronousCompositorExternalBeginFrameSource::BeginFrame() {
+void SynchronousCompositorExternalBeginFrameSource::SendBeginFrameOnDraw() {
   DCHECK(CalledOnValidThread());
-  CallOnBeginFrame(cc::BeginFrameArgs::Create(
-      BEGINFRAME_FROM_HERE, gfx::FrameTime::Now(), base::TimeTicks(),
-      cc::BeginFrameArgs::DefaultInterval(), cc::BeginFrameArgs::SYNCHRONOUS));
+  cc::BeginFrameArgs args = last_begin_frame_args_;

[boliu, 2015/02/11 02:28:14]

What happens if last_begin_frame_args_ is never set?

Probably ok to just return, ie this draw fails without swapping?

+  args.type = cc::BeginFrameArgs::SYNCHRONOUS_DRAW;
+  CallOnBeginFrame(args);
+}
+
+void SynchronousCompositorExternalBeginFrameSource::SendBeginFrameOnAnimate(
+    cc::BeginFrameArgs args) {
+  DCHECK(CalledOnValidThread());
+  last_begin_frame_args_ = args;
+  args.type = cc::BeginFrameArgs::SYNCHRONOUS_ANIMATE;
+  CallOnBeginFrame(args);
 }
 
 void SynchronousCompositorExternalBeginFrameSource::SetCompositor(
@@ -46,9 +54,8 @@ void SynchronousCompositorExternalBeginFrameSource::SetCompositor(
 void SynchronousCompositorExternalBeginFrameSource::OnNeedsBeginFramesChange(
     bool needs_begin_frames) {
   DCHECK(CalledOnValidThread());
-
   if (compositor_)
-    compositor_->NeedsBeginFramesChanged();
+    compositor_->OnNeedsBeginFramesChange(needs_begin_frames);
 }
 
 void SynchronousCompositorExternalBeginFrameSource::SetClientReady() {