Use new Traversal<SVG*Element> API more in SVG code

Source/core/dom/Element.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Peter Kelly (pmk@post.com)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2013 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
@@ skipping 870 matching lines @@
 inline bool isShadowHost(const Node* node)
 {
     return node && node->isElementNode() && toElement(node)->shadow();
 }
 
 inline bool isShadowHost(const Element* element)
 {
     return element && element->shadow();
 }
 
+// These macros do the same as their NODE equivalents but additionally provide a template specialization
+// for isElementOfType<>() so that the Traversal<> API works for these Element types.
+#define DEFINE_ELEMENT_TYPE_CASTS(thisType, predicate) \
+    template <> inline bool isElementOfType<const thisType>(const Element& element) { return element.predicate; } \
+    DEFINE_NODE_TYPE_CASTS(thisType, predicate)
+
+#define DEFINE_ELEMENT_TYPE_CASTS_WITH_FUNCTION(thisType) \
+    template <> inline bool isElementOfType<const thisType>(const Element& element) { return is##thisType(element); } \
+    DEFINE_NODE_TYPE_CASTS_WITH_FUNCTION(thisType)
+
 } // namespace
 
 #endif