Remove some dead code from rendering/ folder

Source/core/rendering/compositing/RenderLayerCompositor.cpp

 /*
  * Copyright (C) 2009, 2010 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 917 matching lines @@
     if (parentLayer) {
         GraphicsLayer* hostingLayer = parentLayer->compositedLayerMapping()->parentForSublayers();
         GraphicsLayer* hostedLayer = childLayer->compositedLayerMapping()->childForSuperlayers();
 
         hostingLayer->addChild(hostedLayer);
     } else {
         childLayer->compositedLayerMapping()->childForSuperlayers()->removeFromParent();
     }
 }
 
-void RenderLayerCompositor::removeCompositedChildren(RenderLayer* layer)
-{
-    ASSERT(layer->hasCompositedLayerMapping());
-
-    GraphicsLayer* hostingLayer = layer->compositedLayerMapping()->parentForSublayers();
-    hostingLayer->removeAllChildren();
-}
-
 void RenderLayerCompositor::frameViewDidChangeLocation(const IntPoint& contentsOffset)
 {
     if (m_overflowControlsHostLayer)
         m_overflowControlsHostLayer->setPosition(contentsOffset);
 }
 
 void RenderLayerCompositor::frameViewDidChangeSize()
 {
     if (m_containerLayer) {
         FrameView* frameView = m_renderView.frameView();
@@ skipping 772 matching lines @@
     } else if (graphicsLayer == m_scrollLayer.get()) {
         name = "LocalFrame Scrolling Layer";
     } else {
         ASSERT_NOT_REACHED();
     }
 
     return name;
 }
 
 } // namespace WebCore