Update modules classes to use OVERRIDE / FINAL when needed

Source/modules/mediastream/MediaStreamTrack.h

Index: Source/modules/mediastream/MediaStreamTrack.h
diff --git a/Source/modules/mediastream/MediaStreamTrack.h b/Source/modules/mediastream/MediaStreamTrack.h
index ad59cdebabe596817a5851e1ef7c16cc34cc9357..051e948a64ff763cfbc2899569fa09d03bd486a7 100644
--- a/Source/modules/mediastream/MediaStreamTrack.h
+++ b/Source/modules/mediastream/MediaStreamTrack.h
@@ -43,7 +43,7 @@ class ExceptionState;
 class MediaStreamComponent;
 class MediaStreamTrackSourcesCallback;
 
-class MediaStreamTrack : public RefCounted<MediaStreamTrack>, public ScriptWrappable, public ActiveDOMObject, public EventTargetWithInlineData, public MediaStreamSource::Observer {
+class MediaStreamTrack FINAL : public RefCounted<MediaStreamTrack>, public ScriptWrappable, public ActiveDOMObject, public EventTargetWithInlineData, public MediaStreamSource::Observer {
     REFCOUNTED_EVENT_TARGET(MediaStreamTrack);
 public:
     static PassRefPtr<MediaStreamTrack> create(ExecutionContext*, MediaStreamComponent*);