Introduce DEFINE_RENDER_OBJECT_TYPE_CASTS to replace manual toRenderFoo, and use it

Source/core/rendering/RenderFileUploadControl.h

 /*
  * Copyright (C) 2006, 2007, 2009, 2012 Apple 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.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 45 matching lines @@
 
     int maxFilenameWidth() const;
 
     virtual PositionWithAffinity positionForPoint(const LayoutPoint&) OVERRIDE FINAL;
 
     HTMLInputElement* uploadButton() const;
 
     bool m_canReceiveDroppedFiles;
 };
 
-inline RenderFileUploadControl* toRenderFileUploadControl(RenderObject* object)
-{
-    ASSERT_WITH_SECURITY_IMPLICATION(!object || object->isFileUploadControl());
-    return static_cast<RenderFileUploadControl*>(object);
-}
-
-inline const RenderFileUploadControl* toRenderFileUploadControl(const RenderObject* object)
-{
-    ASSERT_WITH_SECURITY_IMPLICATION(!object || object->isFileUploadControl());
-    return static_cast<const RenderFileUploadControl*>(object);
-}
-
-// This will catch anyone doing an unnecessary cast.
-void toRenderFileUploadControl(const RenderFileUploadControl*);
+DEFINE_RENDER_OBJECT_TYPE_CASTS(RenderFileUploadControl, isFileUploadControl());
 
 } // namespace WebCore
 
 #endif // RenderFileUploadControl_h