Revert 106606 - Use WebKit compositor in ui::Layer

ui/gfx/compositor/compositor.h

Index: ui/gfx/compositor/compositor.h
===================================================================
--- ui/gfx/compositor/compositor.h	(revision 106614)
+++ ui/gfx/compositor/compositor.h	(working copy)
@@ -107,7 +107,9 @@
   virtual void Blur(const gfx::Rect& bounds) = 0;
 
   // Schedules a redraw of the layer tree associated with this compositor.
-  virtual void ScheduleDraw();
+  void ScheduleDraw() {
+    delegate_->ScheduleDraw();
+  }
 
   // Sets the root of the layer tree drawn by this Compositor.
   // The Compositor does not own the root layer.
@@ -148,8 +150,6 @@
   virtual void OnNotifyEnd() = 0;
 
   virtual void OnWidgetSizeChanged() = 0;
-  virtual void OnRootLayerChanged();
-  virtual void DrawTree();
 
   CompositorDelegate* delegate() { return delegate_; }