[#7] Resubmitted - Pass gfx structs by const ref (gfx::Size)

cc/layers/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_LAYERS_DELEGATED_RENDERER_LAYER_H_
 #define CC_LAYERS_DELEGATED_RENDERER_LAYER_H_
 
 #include "base/containers/hash_tables.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
@@ skipping 15 matching lines @@
       OVERRIDE;
   virtual void SetLayerTreeHost(LayerTreeHost* host) OVERRIDE;
   virtual bool Update(ResourceUpdateQueue* queue,
                       const OcclusionTracker* occlusion) OVERRIDE;
   virtual void PushPropertiesTo(LayerImpl* impl) 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 SetDisplaySize(const gfx::Size& size);
 
   // Called by the DelegatedFrameProvider when a new frame is available to be
   // picked up.
   void ProviderHasNewFrame();
 
  protected:
   DelegatedRendererLayer(
       const scoped_refptr<DelegatedFrameProvider>& frame_provider);
   virtual ~DelegatedRendererLayer();
 
  private:
   scoped_refptr<DelegatedFrameProvider> frame_provider_;
 
   bool should_collect_new_frame_;
 
   DelegatedFrameData* frame_data_;
   gfx::RectF frame_damage_;
 
   gfx::Size display_size_;
 
   scoped_refptr<BlockingTaskRunner> main_thread_runner_;
   base::WeakPtrFactory<DelegatedRendererLayer> weak_ptrs_;
 
   DISALLOW_COPY_AND_ASSIGN(DelegatedRendererLayer);
 };
 
 }  // namespace cc
 
 #endif  // CC_LAYERS_DELEGATED_RENDERER_LAYER_H_