Update XML classes to use OVERRIDE / FINAL when needed

Source/core/xml/XPathVariableReference.h

 /*
  * Copyright 2005 Frerich Raabe <raabe@kde.org>
  *
  * 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
@@ skipping 15 matching lines @@
 #ifndef XPathVariableReference_h
 #define XPathVariableReference_h
 
 #include "core/xml/XPathExpressionNode.h"
 
 namespace WebCore {
 
     namespace XPath {
 
         // Variable references are not used with XPathEvaluator.
-        class VariableReference : public Expression {
+        class VariableReference FINAL : public Expression {
         public:
             explicit VariableReference(const String& name);
         private:
-            virtual Value evaluate() const;
-            virtual Value::Type resultType() const { ASSERT_NOT_REACHED(); return Value::NumberValue; }
+            virtual Value evaluate() const OVERRIDE;
+            virtual Value::Type resultType() const OVERRIDE { ASSERT_NOT_REACHED(); return Value::NumberValue; }
             String m_name;
         };
 
     }
 }
 
 #endif // XPath_VariableReference_H