[#2] Pass gfx structs by const ref (gfx::Rect, gfx::RectF)

cc/resources/resource_update.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_RESOURCES_RESOURCE_UPDATE_H_
 #define CC_RESOURCES_RESOURCE_UPDATE_H_
 
 #include "cc/base/cc_export.h"
 #include "ui/gfx/rect.h"
 #include "ui/gfx/vector2d.h"
 
 class SkBitmap;
 
 namespace cc {
 
 class PrioritizedResource;
 
 struct CC_EXPORT ResourceUpdate {
   static ResourceUpdate Create(PrioritizedResource* resource,
                                const SkBitmap* bitmap,
-                               gfx::Rect content_rect,
-                               gfx::Rect source_rect,
+                               const gfx::Rect& content_rect,
+                               const gfx::Rect& source_rect,
                                gfx::Vector2d dest_offset);
 
   ResourceUpdate();
   virtual ~ResourceUpdate();
 
   PrioritizedResource* texture;
   const SkBitmap* bitmap;
   gfx::Rect content_rect;
   gfx::Rect source_rect;
   gfx::Vector2d dest_offset;
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_RESOURCE_UPDATE_H_