Update rendering classes to use OVERRIDE / FINAL when needed

Source/core/rendering/RenderHTMLCanvas.h

Index: Source/core/rendering/RenderHTMLCanvas.h
diff --git a/Source/core/rendering/RenderHTMLCanvas.h b/Source/core/rendering/RenderHTMLCanvas.h
index 083f6317e76644318af4a57eca23d2fa2a5683da..3c810d24e7d867e28f3bf849a987f5fee5fb3f12 100644
--- a/Source/core/rendering/RenderHTMLCanvas.h
+++ b/Source/core/rendering/RenderHTMLCanvas.h
@@ -36,15 +36,15 @@ class RenderHTMLCanvas FINAL : public RenderReplaced {
 public:
     explicit RenderHTMLCanvas(HTMLCanvasElement*);
 
-    virtual bool isCanvas() const { return true; }
+    virtual bool isCanvas() const OVERRIDE { return true; }
     virtual LayerType layerTypeRequired() const OVERRIDE;
 
     void canvasSizeChanged();
 
 private:
-    virtual const char* renderName() const { return "RenderHTMLCanvas"; }
-    virtual void paintReplaced(PaintInfo&, const LayoutPoint&);
-    virtual void intrinsicSizeChanged() { canvasSizeChanged(); }
+    virtual const char* renderName() const OVERRIDE { return "RenderHTMLCanvas"; }
+    virtual void paintReplaced(PaintInfo&, const LayoutPoint&) OVERRIDE;
+    virtual void intrinsicSizeChanged() OVERRIDE { canvasSizeChanged(); }
 };
 
 DEFINE_RENDER_OBJECT_TYPE_CASTS(RenderHTMLCanvas, isCanvas());