Prefer to forward-declare GraphicsContext in headers.

Source/platform/mac/ScrollAnimatorMac.mm

 /*
  * Copyright (C) 2010, 2011 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 11 matching lines @@
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
  * THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "config.h"
 
 #include "platform/mac/ScrollAnimatorMac.h"
 
 #include "platform/PlatformGestureEvent.h"
 #include "platform/PlatformWheelEvent.h"
-#include "platform/geometry/FloatPoint.h"
+#include "platform/geometry/FloatRect.h"
+#include "platform/geometry/IntRect.h"
 #include "platform/mac/BlockExceptions.h"
 #include "platform/mac/EmptyProtocolDefinitions.h"
 #include "platform/mac/NSScrollerImpDetails.h"
 #include "platform/scroll/ScrollView.h"
 #include "platform/scroll/ScrollableArea.h"
 #include "platform/scroll/ScrollbarTheme.h"
 #include "platform/scroll/ScrollbarThemeMacCommon.h"
 #include "platform/scroll/ScrollbarThemeMacOverlayAPI.h"
 #include "wtf/MainThread.h"
 #include "wtf/PassOwnPtr.h"
@@ skipping 1245 matching lines @@
         return;
 
     m_visibleScrollerThumbRect = rectInViewCoordinates;
 }
 
 bool ScrollAnimatorMac::canUseCoordinatedScrollbar() {
     return ScrollbarThemeMacCommon::isOverlayAPIAvailable();
 }
 
 } // namespace WebCore