Clean up forward declarations in Source/platform

Source/platform/PlatformTouchPoint.h

 /*
     Copyright (C) 2009 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 PlatformTouchPoint_h
 #define PlatformTouchPoint_h
 
 #include "platform/geometry/FloatPoint.h"
 
 namespace blink {
 
-class PlatformTouchEvent;
-
 class PlatformTouchPoint {
 public:
     enum State {
         TouchReleased,
         TouchPressed,
         TouchMoved,
         TouchStationary,
         TouchCancelled,
         TouchStateEnd // Placeholder: must remain the last item.
     };
@@ skipping 20 matching lines @@
     FloatPoint m_screenPos;
     FloatPoint m_pos;
     FloatSize m_radius;
     float m_rotationAngle;
     float m_force;
 };
 
 }
 
 #endif // PlatformTouchPoint_h