Minor cleanups to includes and fwd decls in core/css/resolver

Source/core/css/resolver/StyleAdjuster.h

 /*
  * Copyright (C) 2013 Google, Inc.
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 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
  * 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 StyleAdjuster_h
 #define StyleAdjuster_h
 
 namespace WebCore {
 
 class CachedUAStyle;
-class Document;
 class Element;
 class RenderStyle;
 
 // Certain CSS Properties/Values do not apply to certain elements
 // and the web expects that we expose "adjusted" values when
 // for those property/element pairs.
 class StyleAdjuster {
 public:
     StyleAdjuster(const CachedUAStyle& cachedUAStyle, bool useQuirksModeStyles)
         : m_cachedUAStyle(cachedUAStyle)
         , m_useQuirksModeStyles(useQuirksModeStyles)
     { }
 
     void adjustRenderStyle(RenderStyle* styleToAdjust, RenderStyle* parentStyle, Element*);
 
 private:
     void adjustGridItemPosition(RenderStyle*) const;
 
     const CachedUAStyle& m_cachedUAStyle;
     bool m_useQuirksModeStyles;
 };
 
 } // namespace WebCore
 
 #endif // StyleAdjuster_h