Prevent 'removetrack' events from firing when all inband text tracks are removed.

Source/core/html/track/TextTrackList.h

 /*
  * Copyright (C) 2011, 2012 Apple Inc.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 11 matching lines @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef TextTrackList_h
 #define TextTrackList_h
 
 #include "bindings/v8/ScriptWrappable.h"
 #include "core/events/EventListener.h"
 #include "core/events/EventTarget.h"
+#include "core/html/HTMLMediaElement.h"
 #include "platform/Timer.h"
 #include "wtf/PassRefPtr.h"
 #include "wtf/RefCounted.h"
 #include "wtf/Vector.h"
 
 namespace WebCore {
 
 class GenericEventQueue;
-class HTMLMediaElement;
 class TextTrack;
-class TextTrackList;
 
 class TextTrackList FINAL : public RefCounted<TextTrackList>, public ScriptWrappable, public EventTargetWithInlineData {
     REFCOUNTED_EVENT_TARGET(TextTrackList);
 public:
     static PassRefPtr<TextTrackList> create(HTMLMediaElement* owner)
     {
         return adoptRef(new TextTrackList(owner));
     }
     virtual ~TextTrackList();
 
     unsigned length() const;
     int getTrackIndex(TextTrack*);
     int getTrackIndexRelativeToRenderedTracks(TextTrack*);
     bool contains(TextTrack*) const;
 
     TextTrack* item(unsigned index);
     TextTrack* getTrackById(const AtomicString& id);
     void append(PassRefPtr<TextTrack>);
     void remove(TextTrack*);
 
     // EventTarget
     virtual const AtomicString& interfaceName() const OVERRIDE;
     virtual ExecutionContext* executionContext() const OVERRIDE;
 
     DEFINE_ATTRIBUTE_EVENT_LISTENER(addtrack);
     DEFINE_ATTRIBUTE_EVENT_LISTENER(change);
     DEFINE_ATTRIBUTE_EVENT_LISTENER(removetrack);
 
     void clearOwnerAndClients();
-    Node* owner() const;
+    HTMLMediaElement* owner() const;
 
     void scheduleChangeEvent();
+    void removeAllInbandTracks();
 
 private:
     explicit TextTrackList(HTMLMediaElement*);
 
     void scheduleTrackEvent(const AtomicString& eventName, PassRefPtr<TextTrack>);
 
     void scheduleAddTrackEvent(PassRefPtr<TextTrack>);
     void scheduleRemoveTrackEvent(PassRefPtr<TextTrack>);
 
     void invalidateTrackIndexesAfterTrack(TextTrack*);
 
     HTMLMediaElement* m_owner;
 
     OwnPtr<GenericEventQueue> m_asyncEventQueue;
 
     Vector<RefPtr<TextTrack> > m_addTrackTracks;
     Vector<RefPtr<TextTrack> > m_elementTracks;
     Vector<RefPtr<TextTrack> > m_inbandTracks;
 };
 
 } // namespace WebCore
 
 #endif