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

cc/trees/single_thread_proxy.cc

Index: cc/trees/single_thread_proxy.cc
diff --git a/cc/trees/single_thread_proxy.cc b/cc/trees/single_thread_proxy.cc
index 3390193439535e7b21e6802b6059b7c23a362505..28688fca443bf48d70c30663191c3b08dece26fd 100644
--- a/cc/trees/single_thread_proxy.cc
+++ b/cc/trees/single_thread_proxy.cc
@@ -565,6 +565,10 @@ void SingleThreadProxy::DidSwapBuffersCompleteOnImplThread() {
   layer_tree_host_->DidCompleteSwapBuffers();
 }
 
+void SingleThreadProxy::OnDrawForOutputSurface() {
+  NOTREACHED() << "Implemented by ThreadProxy for synchronous compositor.";
+}
+
 void SingleThreadProxy::CompositeImmediately(base::TimeTicks frame_begin_time) {
   TRACE_EVENT0("cc,benchmark", "SingleThreadProxy::CompositeImmediately");
   DCHECK(Proxy::IsMainThread());
@@ -581,7 +585,7 @@ void SingleThreadProxy::CompositeImmediately(base::TimeTicks frame_begin_time) {
   {
     BeginFrameArgs begin_frame_args(BeginFrameArgs::Create(
         BEGINFRAME_FROM_HERE, frame_begin_time, base::TimeTicks(),
-        BeginFrameArgs::DefaultInterval(), BeginFrameArgs::SYNCHRONOUS));
+        BeginFrameArgs::DefaultInterval(), BeginFrameArgs::NORMAL));
     DoBeginMainFrame(begin_frame_args);
     DoCommit();
 
@@ -915,6 +919,10 @@ void SingleThreadProxy::ScheduledActionPrepareTiles() {
   layer_tree_host_impl_->PrepareTiles();
 }
 
+void SingleThreadProxy::ScheduledActionInvalidateOutputSurface() {
+  NOTREACHED();
+}
+
 void SingleThreadProxy::DidAnticipatedDrawTimeChange(base::TimeTicks time) {
 }