Introduce DEFINE_RENDER_OBJECT_TYPE_CASTS to replace manual toRenderFoo, and use it

Source/core/rendering/RenderLayerModelObject.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2006, 2007, 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2010, 2012 Google Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 59 matching lines @@
 
     RenderLayer* m_layer;
 
     // Used to store state between styleWillChange and styleDidChange
     static bool s_wasFloating;
     static bool s_hadLayer;
     static bool s_hadTransform;
     static bool s_layerWasSelfPainting;
 };
 
-inline RenderLayerModelObject* toRenderLayerModelObject(RenderObject* object)
-{
-    ASSERT_WITH_SECURITY_IMPLICATION(!object || object->isLayerModelObject());
-    return static_cast<RenderLayerModelObject*>(object);
-}
-
-inline const RenderLayerModelObject* toRenderLayerModelObject(const RenderObject* object)
-{
-    ASSERT_WITH_SECURITY_IMPLICATION(!object || object->isLayerModelObject());
-    return static_cast<const RenderLayerModelObject*>(object);
-}
-
-// This will catch anyone doing an unnecessary cast.
-void toRenderLayerModelObject(const RenderLayerModelObject*);
+DEFINE_RENDER_OBJECT_TYPE_CASTS(RenderLayerModelObject, isLayerModelObject());
 
 } // namespace WebCore
 
 #endif // RenderLayerModelObject_h