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

cc/test/tiled_layer_test_common.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/tiled_layer_test_common.h"
 
 namespace cc {
 
 FakeLayerUpdater::Resource::Resource(FakeLayerUpdater* layer,
                                      scoped_ptr<PrioritizedResource> texture)
@@ skipping 17 matching lines @@
     queue->AppendFullUpload(upload);
 
   layer_->Update();
 }
 
 FakeLayerUpdater::FakeLayerUpdater() : prepare_count_(0), update_count_(0) {}
 
 FakeLayerUpdater::~FakeLayerUpdater() {}
 
 void FakeLayerUpdater::PrepareToUpdate(const gfx::Rect& content_rect,
-                                       const gfx::Size& tile_size,
+                                       gfx::Size tile_size,
                                        float contents_width_scale,
                                        float contents_height_scale,
                                        gfx::Rect* resulting_opaque_rect) {
   prepare_count_++;
   last_update_rect_ = content_rect;
   if (!rect_to_invalidate_.IsEmpty()) {
     layer_->InvalidateContentRect(rect_to_invalidate_);
     rect_to_invalidate_ = gfx::Rect();
     layer_ = NULL;
   }
@@ skipping 92 matching lines @@
       ++num;
   }
   num_dependents_need_push_properties_ = num;
 }
 
 LayerUpdater* FakeTiledLayer::Updater() const {
   return fake_updater_.get();
 }
 
 void FakeTiledLayerWithScaledBounds::SetContentBounds(
-    const gfx::Size& content_bounds) {
+    gfx::Size content_bounds) {
   forced_content_bounds_ = content_bounds;
   draw_properties().content_bounds = forced_content_bounds_;
 }
 
 void FakeTiledLayerWithScaledBounds::CalculateContentsScale(
     float ideal_contents_scale,
     float device_scale_factor,
     float page_scale_factor,
     bool animating_transform_to_screen,
     float* contents_scale_x,
     float* contents_scale_y,
     gfx::Size* content_bounds) {
   *contents_scale_x =
       static_cast<float>(forced_content_bounds_.width()) / bounds().width();
   *contents_scale_y =
       static_cast<float>(forced_content_bounds_.height()) / bounds().height();
   *content_bounds = forced_content_bounds_;
 }
 
 }  // namespace cc