Remove a bunch of dead code from RenderLayer

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 715 matching lines @@
     // that need to be painted. That will cause the second pass through the layer tree to run,
     // and we'll paint the scrollbars then. In the meantime, cache tx and ty so that the
     // second pass doesn't need to re-enter the RenderTree to get it right.
     if (hasOverlayScrollbars() && !paintingOverlayControls) {
         m_cachedOverlayScrollbarOffset = paintOffset;
         IntRect localDamgeRect = damageRect;
         localDamgeRect.moveBy(-paintOffset);
         if (!overflowControlsIntersectRect(localDamgeRect))
             return;
 
-        RenderView* renderView = box().view();
-
-        RenderLayer* paintingRoot = layer()->enclosingLayerWithCompositedLayerMapping(IncludeSelf);
-        if (!paintingRoot)
-            paintingRoot = renderView->layer();
-
-        paintingRoot->setContainsDirtyOverlayScrollbars(true);
+        box().view()->layer()->setContainsDirtyOverlayScrollbars(true);
         return;
     }
 
     // This check is required to avoid painting custom CSS scrollbars twice.
     if (paintingOverlayControls && !hasOverlayScrollbars())
         return;
 
     // Now that we're sure the scrollbars are in the right place, paint them.
     if (m_hBar)
         m_hBar->paint(context, damageRect);
@@ skipping 58 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