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

cc/test/fake_picture_layer_tiling_client.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/test/fake_picture_layer_tiling_client.h"
 
 #include <limits>
 
 #include "cc/test/fake_tile_manager.h"
 
@@ skipping 31 matching lines @@
 
 scoped_refptr<Tile> FakePictureLayerTilingClient::CreateTile(
     PictureLayerTiling*,
     const gfx::Rect& rect) {
   if (!allow_create_tile_)
     return scoped_refptr<Tile>();
   return tile_manager_->CreateTile(
       pile_.get(), tile_size_, rect, gfx::Rect(), 1, 0, 0, Tile::USE_LCD_TEXT);
 }
 
-void FakePictureLayerTilingClient::SetTileSize(gfx::Size tile_size) {
+void FakePictureLayerTilingClient::SetTileSize(const gfx::Size& tile_size) {
   tile_size_ = tile_size;
 }
 
 gfx::Size FakePictureLayerTilingClient::CalculateTileSize(
-    gfx::Size /* content_bounds */) const {
+    const gfx::Size& /* content_bounds */) const {
   return tile_size_;
 }
 
 const Region* FakePictureLayerTilingClient::GetInvalidation() {
   return &invalidation_;
 }
 
 const PictureLayerTiling* FakePictureLayerTilingClient::GetTwinTiling(
       const PictureLayerTiling* tiling) const {
   return twin_tiling_;
 }
 
 }  // namespace cc