cc: Without valid frame, delegated renderer layer is not drawable

cc/delegated_renderer_layer.h

Index: cc/delegated_renderer_layer.h
diff --git a/cc/delegated_renderer_layer.h b/cc/delegated_renderer_layer.h
index f8c847d74615eb32cd980e2af0fa960abf170f5b..8266b634264e4809607708089301fc9e8e5ca538 100644
--- a/cc/delegated_renderer_layer.h
+++ b/cc/delegated_renderer_layer.h
@@ -18,6 +18,7 @@ class CC_EXPORT DelegatedRendererLayer : public Layer {
   virtual scoped_ptr<LayerImpl> createLayerImpl(LayerTreeImpl* tree_impl)
       OVERRIDE;
   virtual void pushPropertiesTo(LayerImpl* impl) OVERRIDE;
+  virtual bool drawsContent() const OVERRIDE;
 
   // Set the size at which the frame should be displayed, with the origin at the
   // layer's origin. This must always contain at least the layer's bounds. A
@@ -34,6 +35,7 @@ class CC_EXPORT DelegatedRendererLayer : public Layer {
  private:
   scoped_ptr<DelegatedFrameData> frame_data_;
   gfx::RectF damage_in_frame_;
+  gfx::Size frame_size_;
   gfx::Size display_size_;
 };