Oilpan: add transition types to track interface objects.

Source/core/html/track/TextTrackList.cpp

 /*
  * 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 30 matching lines @@
     , m_asyncEventQueue(GenericEventQueue::create(this))
 {
     ScriptWrappable::init(this);
 }
 
 TextTrackList::~TextTrackList()
 {
     ASSERT(!m_owner);
 
     m_asyncEventQueue->close();
+}
 
+void TextTrackList::dispose()
+{
     for (unsigned i = 0; i < length(); ++i) {
         item(i)->setTrackList(0);

[haraken, 2014/04/22 02:37:47]

Just help me understand: Why do we need to explicitly clear TextTracks in the
list? If HTMLMediaElement holds a persistent reference to TextTrackList, and
TextTrackList and TextTracks in the list have bi-directional strong references,
we won't need to do the explicit clear. When the HTMLMediaElement drops the
persistent reference, both the TextTrackList and TextTracks will be collected in
a next GC at the same time.

[sof, 2014/04/22 06:27:52]

Yes, no need to do the clearing for any of those. The reason it is needed is due
to the comment in
https://codereview.chromium.org/244493002/diff/1/Source/core/html/track/Inban...

i.e., notifying the platform client that the track has gone away needs to
happen, and it looks/ed dicey to delay until the InbandTextTrack object is
finalized.

[haraken, 2014/04/22 06:41:09]

ah, that makes sense. Thanks for the clarification.

     }
 }
 
 unsigned TextTrackList::length() const
 {
     return m_addTrackTracks.size() + m_elementTracks.size() + m_inbandTracks.size();
 }
 
 int TextTrackList::getTrackIndex(TextTrack *textTrack)
 {
@@ skipping 82 matching lines @@
         if (track->id() == id)
             return track;
     }
 
     // When no tracks match the given argument, the method must return null.
     return 0;
 }
 
 void TextTrackList::invalidateTrackIndexesAfterTrack(TextTrack* track)
 {
-    Vector<RefPtr<TextTrack> >* tracks = 0;
+    WillBeHeapVector<RefPtrWillBeMember<TextTrack> >* tracks = 0;
 
     if (track->trackType() == TextTrack::TrackElement) {
         tracks = &m_elementTracks;
         for (size_t i = 0; i < m_addTrackTracks.size(); ++i)
             m_addTrackTracks[i]->invalidateTrackIndex();
         for (size_t i = 0; i < m_inbandTracks.size(); ++i)
             m_inbandTracks[i]->invalidateTrackIndex();
     } else if (track->trackType() == TextTrack::AddTrack) {
         tracks = &m_addTrackTracks;
         for (size_t i = 0; i < m_inbandTracks.size(); ++i)
             m_inbandTracks[i]->invalidateTrackIndex();
     } else if (track->trackType() == TextTrack::InBand)
         tracks = &m_inbandTracks;
     else
         ASSERT_NOT_REACHED();
 
     size_t index = tracks->find(track);
     if (index == kNotFound)
         return;
 
     for (size_t i = index; i < tracks->size(); ++i)
         tracks->at(index)->invalidateTrackIndex();
 }
 
-void TextTrackList::append(PassRefPtr<TextTrack> prpTrack)
+void TextTrackList::append(PassRefPtrWillBeRawPtr<TextTrack> prpTrack)
 {
-    RefPtr<TextTrack> track = prpTrack;
+    RefPtrWillBeRawPtr<TextTrack> track = prpTrack;
 
     if (track->trackType() == TextTrack::AddTrack)
         m_addTrackTracks.append(track);
     else if (track->trackType() == TextTrack::TrackElement) {
         // Insert tracks added for <track> element in tree order.
         size_t index = static_cast<LoadableTextTrack*>(track.get())->trackElementIndex();
         m_elementTracks.insert(index, track);
     } else if (track->trackType() == TextTrack::InBand) {
         // Insert tracks added for in-band in the media file order.
         size_t index = static_cast<InbandTextTrack*>(track.get())->inbandTrackIndex();
         m_inbandTracks.insert(index, track);
     } else
         ASSERT_NOT_REACHED();
 
     invalidateTrackIndexesAfterTrack(track.get());
 
     ASSERT(!track->trackList());
     track->setTrackList(this);
 
     scheduleAddTrackEvent(track.release());
 }
 
 void TextTrackList::remove(TextTrack* track)
 {
-    Vector<RefPtr<TextTrack> >* tracks = 0;
+    WillBeHeapVector<RefPtrWillBeMember<TextTrack> >* tracks = 0;
 
     if (track->trackType() == TextTrack::TrackElement) {
         tracks = &m_elementTracks;
     } else if (track->trackType() == TextTrack::AddTrack) {
         tracks = &m_addTrackTracks;
     } else if (track->trackType() == TextTrack::InBand) {
         tracks = &m_inbandTracks;
     } else {
         ASSERT_NOT_REACHED();
     }
@@ skipping 15 matching lines @@
 void TextTrackList::removeAllInbandTracks()
 {
     for (unsigned i = 0; i < m_inbandTracks.size(); ++i) {
         m_inbandTracks[i]->setTrackList(0);
     }
     m_inbandTracks.clear();
 }
 
 bool TextTrackList::contains(TextTrack* track) const
 {
-    const Vector<RefPtr<TextTrack> >* tracks = 0;
+    const WillBeHeapVector<RefPtrWillBeMember<TextTrack> >* tracks = 0;
 
     if (track->trackType() == TextTrack::TrackElement)
         tracks = &m_elementTracks;
     else if (track->trackType() == TextTrack::AddTrack)
         tracks = &m_addTrackTracks;
     else if (track->trackType() == TextTrack::InBand)
         tracks = &m_inbandTracks;
     else
         ASSERT_NOT_REACHED();
 
     return tracks->find(track) != kNotFound;
 }
 
 const AtomicString& TextTrackList::interfaceName() const
 {
     return EventTargetNames::TextTrackList;
 }
 
 ExecutionContext* TextTrackList::executionContext() const
 {
     ASSERT(m_owner);
     return m_owner->executionContext();
 }
 
 void TextTrackList::clearOwner()
 {
     m_owner = 0;
 }
 
-void TextTrackList::scheduleTrackEvent(const AtomicString& eventName, PassRefPtr<TextTrack> track)
+void TextTrackList::scheduleTrackEvent(const AtomicString& eventName, PassRefPtrWillBeRawPtr<TextTrack> track)
 {
     TrackEventInit initializer;
     initializer.track = track;
     initializer.bubbles = false;
     initializer.cancelable = false;
 
     m_asyncEventQueue->enqueueEvent(TrackEvent::create(eventName, initializer));
 }
 
-void TextTrackList::scheduleAddTrackEvent(PassRefPtr<TextTrack> track)
+void TextTrackList::scheduleAddTrackEvent(PassRefPtrWillBeRawPtr<TextTrack> track)
 {
     // 4.8.10.12.3 Sourcing out-of-band text tracks
     // 4.8.10.12.4 Text track API
     // ... then queue a task to fire an event with the name addtrack, that does not
     // bubble and is not cancelable, and that uses the TrackEvent interface, with
     // the track attribute initialized to the text track's TextTrack object, at
     // the media element's textTracks attribute's TextTrackList object.
     scheduleTrackEvent(EventTypeNames::addtrack, track);
 }
 
 void TextTrackList::scheduleChangeEvent()
 {
     // 4.8.10.12.1 Text track model
     // Whenever a text track that is in a media element's list of text tracks
     // has its text track mode change value, the user agent must run the
     // following steps for the media element:
     // ...
     // Fire a simple event named change at the media element's textTracks
     // attribute's TextTrackList object.
 
     EventInit initializer;
     initializer.bubbles = false;
     initializer.cancelable = false;
 
     m_asyncEventQueue->enqueueEvent(Event::create(EventTypeNames::change, initializer));
 }
 
-void TextTrackList::scheduleRemoveTrackEvent(PassRefPtr<TextTrack> track)
+void TextTrackList::scheduleRemoveTrackEvent(PassRefPtrWillBeRawPtr<TextTrack> track)
 {
     // 4.8.10.12.3 Sourcing out-of-band text tracks
     // When a track element's parent element changes and the old parent was a
     // media element, then the user agent must remove the track element's
     // corresponding text track from the media element's list of text tracks,
     // and then queue a task to fire a trusted event with the name removetrack,
     // that does not bubble and is not cancelable, and that uses the TrackEvent
     // interface, with the track attribute initialized to the text track's
     // TextTrack object, at the media element's textTracks attribute's
     // TextTrackList object.
     scheduleTrackEvent(EventTypeNames::removetrack, track);
 }
 
 HTMLMediaElement* TextTrackList::owner() const
 {
     return m_owner;
 }
+
+void TextTrackList::trace(Visitor* visitor)
+{
+    visitor->trace(m_addTrackTracks);
+    visitor->trace(m_elementTracks);
+    visitor->trace(m_inbandTracks);
+}