cc: Make separate interface for BeginFrame ipc from OutputSurface

cc/test/fake_output_surface.h

Index: cc/test/fake_output_surface.h
diff --git a/cc/test/fake_output_surface.h b/cc/test/fake_output_surface.h
index 306879bbc340091f193f7cbc6bc72dc2a2515832..64fb3b2b1b20f7da47ee6e3107efda958b47663a 100644
--- a/cc/test/fake_output_surface.h
+++ b/cc/test/fake_output_surface.h
@@ -94,9 +94,6 @@ class FakeOutputSurface : public OutputSurface {
 
   virtual void SwapBuffers(CompositorFrame* frame) override;
 
-  virtual void SetNeedsBeginFrame(bool enable) override;
-  bool needs_begin_frame() const { return needs_begin_frame_; }
-
   virtual bool BindToClient(OutputSurfaceClient* client) override;
 
   using OutputSurface::ReleaseGL;
@@ -138,7 +135,6 @@ class FakeOutputSurface : public OutputSurface {
   OutputSurfaceClient* client_;
   CompositorFrame last_sent_frame_;
   size_t num_sent_frames_;
-  bool needs_begin_frame_;
   bool has_external_stencil_test_;
   TransferableResourceArray resources_held_by_parent_;
   scoped_ptr<ManagedMemoryPolicy> memory_policy_to_set_at_bind_;