Clean up forward declarations in Source/core/html

Source/core/html/HTMLMeterElement.h

 /*
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
  *
  * 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
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Library General Public License for more details.
  *
  * You should have received a copy of the GNU Library General Public License
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  *
  */
 
 #ifndef HTMLMeterElement_h
 #define HTMLMeterElement_h
 
 #include "core/html/LabelableElement.h"
 
 namespace blink {
 
-class ExceptionState;
 class MeterValueElement;
 class RenderMeter;
 
 class HTMLMeterElement FINAL : public LabelableElement {
     DEFINE_WRAPPERTYPEINFO();
 public:
     static PassRefPtrWillBeRawPtr<HTMLMeterElement> create(Document&);
 
     enum GaugeRegion {
         GaugeRegionOptimum,
@@ skipping 40 matching lines @@
 
     void didElementStateChange();
     virtual void didAddUserAgentShadowRoot(ShadowRoot&) OVERRIDE;
 
     RefPtrWillBeMember<MeterValueElement> m_value;
 };
 
 } // namespace blink
 
 #endif // HTMLMeterElement_h