Move text track active list management to CueTimeline

Source/core/html/track/TextTrack.h

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  * Copyright (C) 2011, 2012, 2013 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
@@ skipping 16 matching lines @@
 #ifndef TextTrack_h
 #define TextTrack_h
 
 #include "core/events/EventTarget.h"
 #include "core/html/track/TrackBase.h"
 #include "platform/heap/Handle.h"
 #include "wtf/text/WTFString.h"
 
 namespace blink {
 
+class CueTimeline;
 class ExceptionState;
 class HTMLMediaElement;
 class TextTrack;
 class TextTrackCue;
 class TextTrackCueList;
 class TextTrackList;
 class VTTRegion;
 class VTTRegionList;
 
 class TextTrack : public EventTargetWithInlineData, public TrackBase {
@@ skipping 70 matching lines @@
     virtual ExecutionContext* executionContext() const override;
 
     virtual void trace(Visitor*) override;
 
 protected:
     TextTrack(const AtomicString& kind, const AtomicString& label, const AtomicString& language, const AtomicString& id, TextTrackType);
 
     virtual bool isValidKind(const AtomicString& kind) const override { return isValidKindKeyword(kind); }
     virtual AtomicString defaultKind() const override { return subtitlesKeyword(); }
 
+    CueTimeline* cueTimeline() const;
+
     RefPtrWillBeMember<TextTrackCueList> m_cues;
 
 private:
     VTTRegionList* ensureVTTRegionList();
     RefPtrWillBeMember<VTTRegionList> m_regions;
 
     TextTrackCueList* ensureTextTrackCueList();
 
     RawPtrWillBeMember<TextTrackList> m_trackList;
     AtomicString m_mode;
     TextTrackType m_trackType;
     ReadinessState m_readinessState;
     int m_trackIndex;
     int m_renderedTrackIndex;
     bool m_hasBeenConfigured;
 };
 
 DEFINE_TRACK_TYPE_CASTS(TextTrack, TrackBase::TextTrack);
 
 } // namespace blink
 
 #endif // TextTrack_h