Move activeCues ownership to TextTrack

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 61 matching lines @@
     static const AtomicString& showingKeyword();
 
     AtomicString mode() const { return m_mode; }
     virtual void setMode(const AtomicString&);
 
     enum ReadinessState { NotLoaded = 0, Loading = 1, Loaded = 2, FailedToLoad = 3 };
     ReadinessState readinessState() const { return m_readinessState; }
     void setReadinessState(ReadinessState state) { m_readinessState = state; }
 
     TextTrackCueList* cues();
-    TextTrackCueList* activeCues() const;
+    TextTrackCueList* activeCues();
 
     HTMLMediaElement* mediaElement() const;
     Node* owner() const;
 
     void addCue(PassRefPtrWillBeRawPtr<TextTrackCue>);
     void removeCue(TextTrackCue*, ExceptionState&);
 
     VTTRegionList* regions();
     void addRegion(PassRefPtrWillBeRawPtr<VTTRegion>);
     void removeRegion(VTTRegion*, ExceptionState&);
@@ skipping 32 matching lines @@
     virtual bool isValidKind(const AtomicString& kind) const override { return isValidKindKeyword(kind); }
     virtual AtomicString defaultKind() const override { return subtitlesKeyword(); }
 
     void addListOfCues(WillBeHeapVector<RefPtrWillBeMember<TextTrackCue>>&);
 
 private:
     CueTimeline* cueTimeline() const;
 
     TextTrackCueList* ensureTextTrackCueList();
     RefPtrWillBeMember<TextTrackCueList> m_cues;
+    RefPtrWillBeMember<TextTrackCueList> m_activeCues;
 
     VTTRegionList* ensureVTTRegionList();
     RefPtrWillBeMember<VTTRegionList> m_regions;
 
     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