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

cc/quads/io_surface_draw_quad.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_QUADS_IO_SURFACE_DRAW_QUAD_H_
 #define CC_QUADS_IO_SURFACE_DRAW_QUAD_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "cc/base/cc_export.h"
 #include "cc/quads/draw_quad.h"
 #include "ui/gfx/size.h"
 
 namespace cc {
 
 class CC_EXPORT IOSurfaceDrawQuad : public DrawQuad {
  public:
   enum Orientation {
     FLIPPED,
     UNFLIPPED,
     ORIENTATION_LAST = UNFLIPPED
   };
 
   static scoped_ptr<IOSurfaceDrawQuad> Create();
 
   void SetNew(const SharedQuadState* shared_quad_state,
               const gfx::Rect& rect,
               const gfx::Rect& opaque_rect,
-              gfx::Size io_surface_size,
+              const gfx::Size& io_surface_size,
               unsigned io_surface_resource_id,
               Orientation orientation);
 
   void SetAll(const SharedQuadState* shared_quad_state,
               const gfx::Rect& rect,
               const gfx::Rect& opaque_rect,
               const gfx::Rect& visible_rect,
               bool needs_blending,
-              gfx::Size io_surface_size,
+              const gfx::Size& io_surface_size,
               unsigned io_surface_resource_id,
               Orientation orientation);
 
   gfx::Size io_surface_size;
   unsigned io_surface_resource_id;
   Orientation orientation;
 
   virtual void IterateResources(const ResourceIteratorCallback& callback)
       OVERRIDE;
 
   static const IOSurfaceDrawQuad* MaterialCast(const DrawQuad*);
 
  private:
   IOSurfaceDrawQuad();
   virtual void ExtendValue(base::DictionaryValue* value) const OVERRIDE;
 };
 
 }  // namespace cc
 
 #endif  // CC_QUADS_IO_SURFACE_DRAW_QUAD_H_