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

cc/resources/image_layer_updater.cc

 // 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.
 
 #include "cc/resources/image_layer_updater.h"
 #include "cc/resources/prioritized_resource.h"
 #include "cc/resources/resource_update_queue.h"
 
 namespace cc {
 
 ImageLayerUpdater::Resource::Resource(ImageLayerUpdater* updater,
                                       scoped_ptr<PrioritizedResource> texture)
     : LayerUpdater::Resource(texture.Pass()), updater_(updater) {}
 
 ImageLayerUpdater::Resource::~Resource() {}
 
 void ImageLayerUpdater::Resource::Update(ResourceUpdateQueue* queue,
-                                         gfx::Rect source_rect,
+                                         const gfx::Rect& source_rect,
                                          gfx::Vector2d dest_offset,
                                          bool partial_update) {
   updater_->UpdateTexture(
       queue, texture(), source_rect, dest_offset, partial_update);
 }
 
 // static
 scoped_refptr<ImageLayerUpdater> ImageLayerUpdater::Create() {
   return make_scoped_refptr(new ImageLayerUpdater());
 }
 
 scoped_ptr<LayerUpdater::Resource> ImageLayerUpdater::CreateResource(
     PrioritizedResourceManager* manager) {
   return scoped_ptr<LayerUpdater::Resource>(
       new Resource(this, PrioritizedResource::Create(manager)));
 }
 
 void ImageLayerUpdater::UpdateTexture(ResourceUpdateQueue* queue,
                                       PrioritizedResource* texture,
-                                      gfx::Rect source_rect,
+                                      const gfx::Rect& source_rect,
                                       gfx::Vector2d dest_offset,
                                       bool partial_update) {
   // Source rect should never go outside the image pixels, even if this
   // is requested because the texture extends outside the image.
   gfx::Rect clipped_source_rect = source_rect;
   gfx::Rect image_rect = gfx::Rect(0, 0, bitmap_.width(), bitmap_.height());
   clipped_source_rect.Intersect(image_rect);
 
   gfx::Vector2d clipped_dest_offset =
       dest_offset +
@@ skipping 10 matching lines @@
 void ImageLayerUpdater::SetBitmap(const SkBitmap& bitmap) {
   DCHECK(bitmap.pixelRef());
   bitmap_ = bitmap;
 }
 
 bool ImageLayerUpdater::UsingBitmap(const SkBitmap& bitmap) const {
   return bitmap.pixelRef() == bitmap_.pixelRef();
 }
 
 }  // namespace cc