Remove unnecessary includes from dom.

third_party/WebKit/Source/core/dom/TreeWalker.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2000 Frederik Holljen (frederik.holljen@hig.no)
  * Copyright (C) 2001 Peter Kelly (pmk@post.com)
  * Copyright (C) 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2004, 2008 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 11 matching lines @@
  *
  */
 
 #ifndef TreeWalker_h
 #define TreeWalker_h
 
 #include "bindings/core/v8/ScriptWrappable.h"
 #include "core/dom/NodeFilter.h"
 #include "core/dom/NodeIteratorBase.h"
 #include "platform/heap/Handle.h"
-#include "wtf/PassRefPtr.h"
-#include "wtf/RefCounted.h"
 
 namespace blink {
 
 class ExceptionState;
 
 class TreeWalker final : public GarbageCollected<TreeWalker>, public ScriptWrappable, public NodeIteratorBase {
     DEFINE_WRAPPERTYPEINFO();
     USING_GARBAGE_COLLECTED_MIXIN(TreeWalker);
 public:
     static RawPtr<TreeWalker> create(RawPtr<Node> rootNode, unsigned whatToShow, RawPtr<NodeFilter> filter)
@@ skipping 18 matching lines @@
     TreeWalker(RawPtr<Node>, unsigned whatToShow, RawPtr<NodeFilter>);
 
     Node* setCurrent(RawPtr<Node>);
 
     Member<Node> m_current;
 };
 
 } // namespace blink
 
 #endif // TreeWalker_h