Update XML classes to use OVERRIDE / FINAL when needed

Source/core/xml/DocumentXPathEvaluator.h

 /*
  * Copyright (C) 2013, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 18 matching lines @@
 #include "core/dom/DocumentSupplementable.h"
 #include "core/xml/XPathEvaluator.h"
 #include "core/xml/XPathNSResolver.h"
 
 namespace WebCore {
 
 class ExceptionState;
 class XPathExpression;
 class XPathResult;
 
-class DocumentXPathEvaluator : public DocumentSupplement {
+class DocumentXPathEvaluator FINAL : public DocumentSupplement {
 public:
     virtual ~DocumentXPathEvaluator();
 
     static DocumentXPathEvaluator* from(DocumentSupplementable*);
 
     static PassRefPtr<XPathExpression> createExpression(DocumentSupplementable*,
         const String& expression, PassRefPtr<XPathNSResolver>, ExceptionState&);
     static PassRefPtr<XPathNSResolver> createNSResolver(DocumentSupplementable*, Node* nodeResolver);
     static PassRefPtr<XPathResult> evaluate(DocumentSupplementable*,
         const String& expression, Node* contextNode, PassRefPtr<XPathNSResolver>,
         unsigned short type, XPathResult*, ExceptionState&);
 
 private:
     DocumentXPathEvaluator();
 
     static const char* supplementName() { return "DocumentXPathEvaluator"; }
 
     RefPtr<XPathEvaluator> m_xpathEvaluator;
 };
 
 } // namespace WebCore
 
 #endif // DocumentXPathEvaluator_h