Prefer to forward-declare GraphicsContext in headers.

Source/core/rendering/InlineTextBox.h

 /*
  * (C) 1999 Lars Knoll (knoll@kde.org)
  * (C) 2000 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 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 InlineTextBox_h
 #define InlineTextBox_h
 
 #include "core/rendering/InlineBox.h"
 #include "core/rendering/RenderText.h" // so textRenderer() can be inline
-#include "platform/graphics/GraphicsContext.h"
 #include "platform/text/TextRun.h"
 #include "wtf/Forward.h"
 
 namespace WebCore {
 
 struct CompositionUnderline;
 class DocumentMarker;
+class GraphicsContext;
 
 const unsigned short cNoTruncation = USHRT_MAX;
 const unsigned short cFullTruncation = USHRT_MAX - 1;
 
 // Helper functions shared by InlineTextBox / SVGRootInlineBox
 void updateGraphicsContext(GraphicsContext*, const Color& fillColor, const Color& strokeColor, float strokeThickness, ColorSpace);
 Color correctedTextColor(Color textColor, Color backgroundColor);
 
 class InlineTextBox : public InlineBox {
 public:
@@ skipping 160 matching lines @@
 
 inline AffineTransform InlineTextBox::rotation(const FloatRect& boxRect, RotationDirection rotationDirection)
 {
     return rotationDirection == Clockwise ? AffineTransform(0, 1, -1, 0, boxRect.x() + boxRect.maxY(), boxRect.maxY() - boxRect.x())
         : AffineTransform(0, -1, 1, 0, boxRect.x() - boxRect.maxY(), boxRect.x() + boxRect.maxY());
 }
 
 } // namespace WebCore
 
 #endif // InlineTextBox_h