Remove unnecessary includes from dom.

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

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef NthIndexCache_h
 #define NthIndexCache_h
 
 #include "core/CoreExport.h"
 #include "core/dom/Element.h"
 #include "platform/heap/Handle.h"
 #include "wtf/HashMap.h"
-#include "wtf/OwnPtr.h"
-#include "wtf/RefPtr.h"
 
 namespace blink {
 
 class Document;
 
 class CORE_EXPORT NthIndexData final : public GarbageCollected<NthIndexData> {
     WTF_MAKE_NONCOPYABLE(NthIndexData);
 public:
     NthIndexData(ContainerNode&);
     NthIndexData(ContainerNode&, const QualifiedName& type);
@@ skipping 37 matching lines @@
     Member<ParentMapForType> m_parentMapForType;
 
 #if ENABLE(ASSERT)
     uint64_t m_domTreeVersion;
 #endif
 };
 
 } // namespace blink
 
 #endif // NthIndexCache_h