Eliminate calls to TextTrackCue::setIsActive outside of CueTimeline

Source/core/html/track/TextTrackCueList.cpp

 /*
  * Copyright (C) 2011 Google 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 110 matching lines @@
     // make it more difficult to maintain the invariant, so should probably
     // just invalidate here as well.
     return true;
 }
 
 void TextTrackCueList::updateCueIndex(TextTrackCue* cue)
 {
     if (!remove(cue))
         return;
 
-    cue->setIsActive(false);
-    cue->removeDisplayTree();
-
     // FIXME: If moving the cue such that its index in list increases, then
     // what happens with the cached index on cues in the range [oldIndex,
     // newIndex)? (Some of the indices will be "safe", but there'll be a risk
     // that the lazy update via cueIndex() yields duplicates/incorrect order.)
     add(cue);
 }
 
 void TextTrackCueList::clear()
 {
     m_list.clear();
 }
 
 void TextTrackCueList::invalidateCueIndexes(size_t start)
 {
     // FIXME: When iterating cues we could as well update their cached indices too.
     for (size_t i = start; i < m_list.size(); ++i)
         m_list[i]->invalidateCueIndex();
 }
 
 DEFINE_TRACE(TextTrackCueList)
 {
     visitor->trace(m_list);
     visitor->trace(m_activeCues);
 }
 
 } // namespace blink