cc: Make separate interface for BeginFrame ipc from OutputSurface

cc/test/fake_output_surface_client.cc

Index: cc/test/fake_output_surface_client.cc
diff --git a/cc/test/fake_output_surface_client.cc b/cc/test/fake_output_surface_client.cc
index 77c7f8a208283623ced2367926d251d2af43d2a1..073a29f81bfe663ed09805603452d486546d5b6d 100644
--- a/cc/test/fake_output_surface_client.cc
+++ b/cc/test/fake_output_surface_client.cc
@@ -16,10 +16,6 @@ void FakeOutputSurfaceClient::ReleaseGL() {
     output_surface_->ReleaseContextProvider();
 }
 
-void FakeOutputSurfaceClient::BeginFrame(const BeginFrameArgs& args) {
-  begin_frame_count_++;
-}
-
 void FakeOutputSurfaceClient::DidSwapBuffers() {
   swap_count_++;
 }