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

cc/trees/layer_tree_host_impl_unittest.cc

Index: cc/trees/layer_tree_host_impl_unittest.cc
diff --git a/cc/trees/layer_tree_host_impl_unittest.cc b/cc/trees/layer_tree_host_impl_unittest.cc
index 75f753183df09286a7d180151da80538a25161aa..d7470f339e7a85573faed06fd0ad5a11108656dd 100644
--- a/cc/trees/layer_tree_host_impl_unittest.cc
+++ b/cc/trees/layer_tree_host_impl_unittest.cc
@@ -133,6 +133,7 @@ class LayerTreeHostImplTest : public testing::Test,
   void SetNeedsRedrawRectOnImplThread(const gfx::Rect& damage_rect) override {
     did_request_redraw_ = true;
   }
+  void OutputSurfaceDidRequestDraw() override {}
   void SetNeedsAnimateOnImplThread() override { did_request_animate_ = true; }
   void SetNeedsPrepareTilesOnImplThread() override {
     did_request_prepare_tiles_ = true;