cc: Don't pass simple well-defined classes by reference.

cc/resources/scoped_resource.h

 // 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.
 
 #ifndef CC_RESOURCES_SCOPED_RESOURCE_H_
 #define CC_RESOURCES_SCOPED_RESOURCE_H_
 
 #include "base/basictypes.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "cc/base/cc_export.h"
 #include "cc/resources/resource.h"
 
 #ifndef NDEBUG
 #include "base/threading/platform_thread.h"
 #endif
 
 namespace cc {
 
 class CC_EXPORT ScopedResource : public Resource {
  public:
   static scoped_ptr<ScopedResource> create(
       ResourceProvider* resource_provider) {
     return make_scoped_ptr(new ScopedResource(resource_provider));
   }
   virtual ~ScopedResource();
 
-  bool Allocate(const gfx::Size&, GLenum format,
-                ResourceProvider::TextureUsageHint);
+  bool Allocate(gfx::Size size,
+                GLenum format,
+                ResourceProvider::TextureUsageHint hint);
   void Free();
   void Leak();
 
  protected:
   explicit ScopedResource(ResourceProvider* provider);
 
  private:
   ResourceProvider* resource_provider_;
 
 #ifndef NDEBUG
   base::PlatformThreadId allocate_thread_id_;
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(ScopedResource);
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_SCOPED_RESOURCE_H_