cc: Defer first OutputSurface creation until client is ready

cc/trees/single_thread_proxy.h

Index: cc/trees/single_thread_proxy.h
diff --git a/cc/trees/single_thread_proxy.h b/cc/trees/single_thread_proxy.h
index 50e6bf25c82a8767f955514a451dbeebdce523f7..2d9c6478032bfa5fbf707bab579e198200ee0751 100644
--- a/cc/trees/single_thread_proxy.h
+++ b/cc/trees/single_thread_proxy.h
@@ -44,7 +44,7 @@ class SingleThreadProxy : public Proxy, LayerTreeHostImplClient {
   virtual bool CommitRequested() const OVERRIDE;
   virtual bool BeginMainFrameRequested() const OVERRIDE;
   virtual void MainThreadHasStoppedFlinging() OVERRIDE {}
-  virtual void Start(scoped_ptr<OutputSurface> first_output_surface) OVERRIDE;
+  virtual void Start() OVERRIDE;
   virtual void Stop() OVERRIDE;
   virtual size_t MaxPartialTextureUpdates() const OVERRIDE;
   virtual void AcquireLayerTextures() OVERRIDE {}
@@ -108,10 +108,6 @@ class SingleThreadProxy : public Proxy, LayerTreeHostImplClient {
   LayerTreeHostSingleThreadClient* client_;
   bool created_offscreen_context_provider_;
 
-  // Holds the first output surface passed from Start. Should not be used for
-  // anything else.
-  scoped_ptr<OutputSurface> first_output_surface_;
-
   // Used on the Thread, but checked on main thread during
   // initialization/shutdown.
   scoped_ptr<LayerTreeHostImpl> layer_tree_host_impl_;