Introduce DEFINE_RENDER_OBJECT_TYPE_CASTS to replace manual toRenderFoo, and use it

Source/core/rendering/svg/RenderSVGViewportContainer.h

 /*
  * Copyright (C) 2004, 2005, 2007 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005, 2007 Rob Buis <buis@kde.org>
  * Copyright (C) 2009 Google, Inc.
  * Copyright (C) 2009 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.
@@ skipping 44 matching lines @@
     virtual void applyViewportClip(PaintInfo&);
     virtual bool pointIsInsideViewportClip(const FloatPoint& pointInParent);
 
     FloatRect m_viewport;
     mutable AffineTransform m_localToParentTransform;
     bool m_didTransformToRootUpdate : 1;
     bool m_isLayoutSizeChanged : 1;
     bool m_needsTransformUpdate : 1;
 };
 
-inline RenderSVGViewportContainer* toRenderSVGViewportContainer(RenderObject* object)
-{
-    ASSERT_WITH_SECURITY_IMPLICATION(!object || object->isSVGViewportContainer());
-    return static_cast<RenderSVGViewportContainer*>(object);
-}
-
-inline const RenderSVGViewportContainer* toRenderSVGViewportContainer(const RenderObject* object)
-{
-    ASSERT_WITH_SECURITY_IMPLICATION(!object || object->isSVGViewportContainer());
-    return static_cast<const RenderSVGViewportContainer*>(object);
-}
-
-// This will catch anyone doing an unnecessary cast.
-void toRenderSVGViewportContainer(const RenderSVGViewportContainer*);
+DEFINE_RENDER_OBJECT_TYPE_CASTS(RenderSVGViewportContainer, isSVGViewportContainer());
 
 } // namespace WebCore
 
 #endif // RenderSVGViewportContainer_h