Add "change" and "removetrack" events to TextTrackList.

Source/core/html/track/TextTrackList.cpp

Index: Source/core/html/track/TextTrackList.cpp
diff --git a/Source/core/html/track/TextTrackList.cpp b/Source/core/html/track/TextTrackList.cpp
index cc3cbaa69c3ba5f4bb6a1c847fda6b9b95a73448..cea563750d78d429f6c4346c3f3eb358a524f225 100644
--- a/Source/core/html/track/TextTrackList.cpp
+++ b/Source/core/html/track/TextTrackList.cpp
@@ -210,6 +210,8 @@ void TextTrackList::remove(TextTrack* track)
 
     if (inbandTrack)
         inbandTrack->trackRemoved();
+
+    scheduleRemoveTrackEvent(track);
 }
 
 bool TextTrackList::contains(TextTrack* track) const
@@ -259,6 +261,48 @@ void TextTrackList::scheduleAddTrackEvent(PassRefPtr<TextTrack> track)
         m_pendingEventTimer.startOneShot(0);
 }
 
+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_pendingEvents.append(Event::create(EventTypeNames::change, initializer));
+    if (!m_pendingEventTimer.isActive())
+        m_pendingEventTimer.startOneShot(0);
+}
+
+void TextTrackList::scheduleRemoveTrackEvent(PassRefPtr<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.
+
+    RefPtr<TrackBase> trackRef = track;

[acolwell GONE FROM CHROMIUM, 2013/11/22 23:47:58]

nit: Please move this to a scheduleTrackEvent(const AtomicString&, TextTrack*)
helper function to avoid duplicate code.

+    TrackEventInit initializer;
+    initializer.track = trackRef;
+    initializer.bubbles = false;
+    initializer.cancelable = false;
+
+    m_pendingEvents.append(TrackEvent::create(EventTypeNames::removetrack, initializer));

[acolwell GONE FROM CHROMIUM, 2013/11/22 23:47:58]

m_pendingEvents & m_pendingEventTimer should really be replaced with a
GenericEventQueue so you don't have to worry about the startOneShot() business
below.

+    if (!m_pendingEventTimer.isActive())
+        m_pendingEventTimer.startOneShot(0);
+}
+
 void TextTrackList::asyncEventTimerFired(Timer<TextTrackList>*)
 {
     Vector<RefPtr<Event> > pendingEvents;