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

cc/delegated_renderer_layer.h

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CC_DELEGATED_RENDERER_LAYER_H_
 #define CC_DELEGATED_RENDERER_LAYER_H_
 
 #include "cc/cc_export.h"
 #include "cc/layer.h"
 
 namespace cc {
 class DelegatedFrameData;
 
 class CC_EXPORT DelegatedRendererLayer : public Layer {
  public:
   static scoped_refptr<DelegatedRendererLayer> Create();
 
   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
   // value of (0, 0) implies that the frame should be displayed to fit exactly
   // in the layer's bounds.
   void SetDisplaySize(gfx::Size size);
 
   void SetFrameData(scoped_ptr<DelegatedFrameData> frame_data);
 
  protected:
   DelegatedRendererLayer();
   virtual ~DelegatedRendererLayer();
 
  private:
   scoped_ptr<DelegatedFrameData> frame_data_;
   gfx::RectF damage_in_frame_;
+  gfx::Size frame_size_;
   gfx::Size display_size_;
 };
 
 }
 #endif  // CC_DELEGATED_RENDERER_LAYER_H_