Move activeCues ownership to TextTrack

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 44 matching lines @@
 
 TextTrackCue* TextTrackCueList::getCueById(const AtomicString& id) const
 {
     for (size_t i = 0; i < m_list.size(); ++i) {
         if (m_list[i]->id() == id)
             return m_list[i].get();
     }
     return nullptr;
 }
 
-TextTrackCueList* TextTrackCueList::activeCues()
+void TextTrackCueList::collectActiveCues(TextTrackCueList& activeCues) const
 {
-    if (!m_activeCues)
-        m_activeCues = create();
-
-    m_activeCues->clear();
-    for (size_t i = 0; i < m_list.size(); ++i) {
-        RefPtrWillBeRawPtr<TextTrackCue> cue = m_list[i];
+    activeCues.clear();
+    for (auto& cue : m_list) {
         if (cue->isActive())
-            m_activeCues->add(cue);
+            activeCues.add(cue);
     }
-    return m_activeCues.get();
 }
 
 bool TextTrackCueList::add(PassRefPtrWillBeRawPtr<TextTrackCue> cue)
 {
     ASSERT(cue->startTime() >= 0);
     ASSERT(cue->endTime() >= 0);
 
     // Maintain text track cue order:
     // https://html.spec.whatwg.org/#text-track-cue-order
     size_t index = findInsertionIndex(cue.get());
@@ skipping 59 matching lines @@
 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