Update rendering classes to use OVERRIDE / FINAL when needed

Source/core/rendering/CompositedLayerMapping.h

Index: Source/core/rendering/CompositedLayerMapping.h
diff --git a/Source/core/rendering/CompositedLayerMapping.h b/Source/core/rendering/CompositedLayerMapping.h
index 8970f5b1651b01002e6de6ede01667a1e6264645..875a7d55c7fe16242bd77e13386bdd67e3a01064 100644
--- a/Source/core/rendering/CompositedLayerMapping.h
+++ b/Source/core/rendering/CompositedLayerMapping.h
@@ -73,7 +73,7 @@ struct GraphicsLayerPaintInfo {
 //
 // Currently (Oct. 2013) there is one CompositedLayerMapping for each RenderLayer,
 // but this is likely to evolve soon.
-class CompositedLayerMapping : public GraphicsLayerClient {
+class CompositedLayerMapping FINAL : public GraphicsLayerClient {
     WTF_MAKE_NONCOPYABLE(CompositedLayerMapping); WTF_MAKE_FAST_ALLOCATED;
 public:
     explicit CompositedLayerMapping(RenderLayer*);
@@ -173,7 +173,7 @@ public:
     PassOwnPtr<Vector<FloatRect> > collectTrackedRepaintRects() const;
 
 #ifndef NDEBUG
-    virtual void verifyNotPainting();
+    virtual void verifyNotPainting() OVERRIDE;
 #endif
 
     LayoutRect contentsBox() const;