Remove duplicated headers from core/

Source/core/xml/XPathParser.cpp

 /*
  * Copyright 2005 Maksim Orlovich <maksim@kde.org>
  * Copyright (C) 2006 Apple Computer, Inc.
  * Copyright (C) 2007 Alexey Proskuryakov <ap@webkit.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
@@ skipping 16 matching lines @@
 
 #include "config.h"
 #include "core/xml/XPathParser.h"
 
 #include "bindings/v8/ExceptionMessages.h"
 #include "bindings/v8/ExceptionState.h"
 #include "core/dom/ExceptionCode.h"
 #include "core/xml/XPathEvaluator.h"
 #include "core/xml/XPathNSResolver.h"
 #include "core/xml/XPathPath.h"
-#include "core/xml/XPathStep.h"
 #include "wtf/StdLibExtras.h"
 #include "wtf/text/StringHash.h"
 
 using namespace WebCore;
 using namespace WTF;
 using namespace Unicode;
 using namespace XPath;
 
 extern int xpathyyparse(WebCore::XPath::Parser*);
 #include "XPathGrammar.h"
@@ skipping 569 matching lines @@
 {
     if (t == 0)
         return;
 
     ASSERT(m_nodeTests.contains(t));
 
     m_nodeTests.remove(t);
     delete t;
 }