Update remaining HTML classes to use OVERRIDE / FINAL when needed

Source/core/html/shadow/MediaControlElements.h

Index: Source/core/html/shadow/MediaControlElements.h
diff --git a/Source/core/html/shadow/MediaControlElements.h b/Source/core/html/shadow/MediaControlElements.h
index 60cf7de6a60aafffdec5cbe93b82e84f7a6ea949..bb43349ce0e511bdbe8df0b346dbd124f638f5ba 100644
--- a/Source/core/html/shadow/MediaControlElements.h
+++ b/Source/core/html/shadow/MediaControlElements.h
@@ -203,7 +203,7 @@ public:
 
     virtual bool willRespondToMouseClickEvents() OVERRIDE { return true; }
 
-    virtual void setIsFullscreen(bool);
+    void setIsFullscreen(bool);
 
 private:
     explicit MediaControlFullscreenButtonElement(Document&);
@@ -259,7 +259,7 @@ private:
     explicit MediaControlTextTrackContainerElement(Document&);
     virtual const AtomicString& shadowPseudoId() const OVERRIDE;
 
-    virtual RenderObject* createRenderer(RenderStyle*);
+    virtual RenderObject* createRenderer(RenderStyle*) OVERRIDE;
 
     IntRect m_videoDisplaySize;
     float m_fontSize;