Remove more mouse-specific code

sky/engine/core/rendering/RenderLayerScrollableArea.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
  *
  * Portions are Copyright (C) 1998 Netscape Communications Corporation.
  *
  * Other contributors:
  *   Robert O'Callahan <roc+@cs.cmu.edu>
  *   David Baron <dbaron@fas.harvard.edu>
  *   Christian Biesinger <cbiesinger@web.de>
  *   Randall Jesup <rjesup@wgate.com>
@@ skipping 246 matching lines @@
 IntSize RenderLayerScrollableArea::contentsSize() const
 {
     return IntSize(scrollWidth(), scrollHeight());
 }
 
 IntSize RenderLayerScrollableArea::overhangAmount() const
 {
     return IntSize();
 }
 
-IntPoint RenderLayerScrollableArea::lastKnownMousePosition() const
-{
-    return box().frame() ? box().frame()->eventHandler().lastKnownMousePosition() : IntPoint();
-}
-
 IntRect RenderLayerScrollableArea::scrollableAreaBoundingBox() const
 {
     return box().absoluteBoundingBoxRect();
 }
 
 bool RenderLayerScrollableArea::userInputScrollable(ScrollbarOrientation orientation) const
 {
     EOverflow overflowStyle = (orientation == HorizontalScrollbar) ?
         box().style()->overflowX() : box().style()->overflowY();
     return (overflowStyle == OSCROLL || overflowStyle == OAUTO || overflowStyle == OOVERLAY);
@@ skipping 414 matching lines @@
 void RenderLayerScrollableArea::setTopmostScrollChild(RenderLayer* scrollChild)
 {
     // We only want to track the topmost scroll child for scrollable areas with
     // overlay scrollbars.
     if (!hasOverlayScrollbars())
         return;
     m_nextTopmostScrollChild = scrollChild;
 }
 
 } // namespace blink