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

cc/test/layer_tree_pixel_test.cc

 // Copyright 2013 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/layer_tree_pixel_test.h"
 
 #include "base/command_line.h"
 #include "base/path_service.h"
 #include "cc/base/switches.h"
 #include "cc/layers/solid_color_layer.h"
@@ skipping 210 matching lines @@
 
 void LayerTreePixelTest::SetupTree() {
   scoped_refptr<Layer> root = Layer::Create();
   root->SetBounds(content_root_->bounds());
   root->AddChild(content_root_);
   layer_tree_host()->SetRootLayer(root);
   LayerTreeTest::SetupTree();
 }
 
 scoped_ptr<SkBitmap> LayerTreePixelTest::CopyTextureMailboxToBitmap(
-    gfx::Size size,
+    const gfx::Size& size,
     const TextureMailbox& texture_mailbox) {
   DCHECK(texture_mailbox.IsTexture());
   if (!texture_mailbox.IsTexture())
     return scoped_ptr<SkBitmap>();
 
   scoped_ptr<gpu::GLInProcessContext> context = CreateTestInProcessContext();
   GLES2Interface* gl = context->GetImplementation();
 
   if (texture_mailbox.sync_point())
     gl->WaitSyncPointCHROMIUM(texture_mailbox.sync_point());
@@ skipping 129 matching lines @@
 
   *texture_mailbox = TextureMailbox(mailbox, sync_point);
   *release_callback = SingleReleaseCallback::Create(
       base::Bind(&LayerTreePixelTest::ReleaseTextureMailbox,
                  base::Unretained(this),
                  base::Passed(&context),
                  texture_id));
 }
 
 }  // namespace cc