Clean up forward declarations in Source/platform

Source/platform/PlatformWheelEvent.h

 /*
  * Copyright (C) 2004, 2005, 2006, 2009 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 13 matching lines @@
  */
 
 #ifndef PlatformWheelEvent_h
 #define PlatformWheelEvent_h
 
 #include "platform/PlatformEvent.h"
 #include "platform/geometry/IntPoint.h"
 
 namespace blink {
 
-class FloatPoint;
-class FloatSize;
-
 // Wheel events come in two flavors:
 // The ScrollByPixelWheelEvent is a fine-grained event that specifies the precise number of pixels to scroll. It is sent directly by MacBook touchpads on OS X,
 // and synthesized in other cases where platforms generate line-by-line scrolling events.
 // The ScrollByPageWheelEvent indicates that the wheel event should scroll an entire page. In this case WebCore's built in paging behavior is used to page
 // up and down (you get the same behavior as if the user was clicking in a scrollbar track to page up or page down).
 enum PlatformWheelEventGranularity {
     ScrollByPageWheelEvent,
     ScrollByPixelWheelEvent,
 };
 
@@ skipping 95 matching lines @@
     float m_unacceleratedScrollingDeltaX;
     float m_unacceleratedScrollingDeltaY;
     bool m_canRubberbandLeft;
     bool m_canRubberbandRight;
 #endif
 };
 
 } // namespace blink
 
 #endif // PlatformWheelEvent_h