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

cc/resources/texture_mailbox.h

 // 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.
 
 #ifndef CC_RESOURCES_TEXTURE_MAILBOX_H_
 #define CC_RESOURCES_TEXTURE_MAILBOX_H_
 
 #include <string>
 
 #include "base/callback.h"
@@ skipping 10 matching lines @@
  public:
   TextureMailbox();
   explicit TextureMailbox(const std::string& mailbox_name);
   explicit TextureMailbox(const gpu::Mailbox& mailbox_name);
   TextureMailbox(const gpu::Mailbox& mailbox_name,
                  unsigned sync_point);
   TextureMailbox(const gpu::Mailbox& mailbox_name,
                  unsigned texture_target,
                  unsigned sync_point);
   TextureMailbox(base::SharedMemory* shared_memory,
-                 gfx::Size size);
+                 const gfx::Size& size);
 
   ~TextureMailbox();
 
   bool IsValid() const { return IsTexture() || IsSharedMemory(); }
   bool IsTexture() const { return !name_.IsZero(); }
   bool IsSharedMemory() const { return shared_memory_ != NULL; }
 
   bool Equals(const TextureMailbox&) const;
   bool ContainsMailbox(const gpu::Mailbox&) const;
   bool ContainsHandle(base::SharedMemoryHandle handle) const;
@@ skipping 16 matching lines @@
   gpu::Mailbox name_;
   unsigned target_;
   unsigned sync_point_;
   base::SharedMemory* shared_memory_;
   gfx::Size shared_memory_size_;
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_TEXTURE_MAILBOX_H_