Apply FINAL to the RenderObject hierarchy.

Source/core/rendering/RenderWidget.h

Index: Source/core/rendering/RenderWidget.h
diff --git a/Source/core/rendering/RenderWidget.h b/Source/core/rendering/RenderWidget.h
index ef8f3b74179d8c5804e90ce787c56fd45986af59..f825141fd2e331773f7a4a688848de400d19aa6e 100644
--- a/Source/core/rendering/RenderWidget.h
+++ b/Source/core/rendering/RenderWidget.h
@@ -79,7 +79,7 @@ protected:
 
     void clearWidget();
 
-    virtual void styleDidChange(StyleDifference, const RenderStyle* oldStyle);
+    virtual void styleDidChange(StyleDifference, const RenderStyle* oldStyle) OVERRIDE FINAL;
     virtual void layout();
     virtual void paint(PaintInfo&, const LayoutPoint&);
     virtual CursorDirective getCursor(const LayoutPoint&, Cursor&) const;
@@ -88,12 +88,12 @@ protected:
     virtual void paintContents(PaintInfo&, const LayoutPoint&);
 
 private:
-    virtual bool isWidget() const { return true; }
+    virtual bool isWidget() const OVERRIDE FINAL { return true; }
 
-    virtual void willBeDestroyed();
-    virtual void destroy();
-    virtual void setSelectionState(SelectionState);
-    virtual void setOverlapTestResult(bool);
+    virtual void willBeDestroyed() OVERRIDE FINAL;
+    virtual void destroy() OVERRIDE FINAL;
+    virtual void setSelectionState(SelectionState) OVERRIDE FINAL;
+    virtual void setOverlapTestResult(bool) OVERRIDE FINAL;
 
     bool setWidgetGeometry(const LayoutRect&);
     bool updateWidgetGeometry();