cc: Measure compositor timing with finer granularity

cc/test/fake_layer_tree_host_impl_client.h

Index: cc/test/fake_layer_tree_host_impl_client.h
diff --git a/cc/test/fake_layer_tree_host_impl_client.h b/cc/test/fake_layer_tree_host_impl_client.h
index 4085733f8476714e753df339862c5615290cf0c6..ebb8ae5ecf9ab3af8992ddd37f628d3b6d841c71 100644
--- a/cc/test/fake_layer_tree_host_impl_client.h
+++ b/cc/test/fake_layer_tree_host_impl_client.h
@@ -40,6 +40,7 @@ class FakeLayerTreeHostImplClient : public LayerTreeHostImplClient {
   void PostDelayedAnimationTaskOnImplThread(const base::Closure& task,
                                             base::TimeDelta delay) override {}
   void DidActivateSyncTree() override {}
+  void WillPrepareTiles() override {}
   void DidPrepareTiles() override {}
   void DidCompletePageScaleAnimationOnImplThread() override {}
   void OnDrawForOutputSurface() override {}