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 b1248e005f8b3ff52c80a5f60f255816e577c0c4..c2de0bc6fb9f56c7e377c88e108fdc14b6d78f9e 100644
--- a/cc/trees/single_thread_proxy.cc
+++ b/cc/trees/single_thread_proxy.cc
@@ -366,6 +366,12 @@ void SingleThreadProxy::SetNeedsRedrawOnImplThread() {
     scheduler_on_impl_thread_->SetNeedsRedraw();
 }
 
+void SingleThreadProxy::OutputSurfaceDidRequestDraw() {
+  TRACE_EVENT0("cc", "SingleThreadProxy::OutputSurfaceDidRequestDraw");
+  if (scheduler_on_impl_thread_)
+    scheduler_on_impl_thread_->OutputSurfaceDidRequestDraw();
+}
+
 void SingleThreadProxy::SetNeedsAnimateOnImplThread() {
   client_->ScheduleComposite();
   if (scheduler_on_impl_thread_)
@@ -778,6 +784,11 @@ void SingleThreadProxy::ScheduledActionPrepareTiles() {
   layer_tree_host_impl_->PrepareTiles();
 }
 
+void SingleThreadProxy::ScheduledActionInvalidateOutputSurface() {
+  DCHECK(layer_tree_host_impl_->output_surface());
+  layer_tree_host_impl_->output_surface()->Invalidate();
+}
+
 void SingleThreadProxy::DidAnticipatedDrawTimeChange(base::TimeTicks time) {
 }