Initial implementation of AudioTrack, AudioTrackList, VideoTrack, and VideoTrackList.

Source/core/html/HTMLMediaElement.h

Index: Source/core/html/HTMLMediaElement.h
diff --git a/Source/core/html/HTMLMediaElement.h b/Source/core/html/HTMLMediaElement.h
index ff834bbc591634b5ed972592a091bd75d8333fb5..90bb63d57a7fb0d92a53030937b499ab3dd5024e 100644
--- a/Source/core/html/HTMLMediaElement.h
+++ b/Source/core/html/HTMLMediaElement.h
@@ -49,6 +49,7 @@ namespace WebCore {
 class AudioSourceProvider;
 class MediaElementAudioSourceNode;
 #endif
+class AudioTrackList;
 class ContentType;
 class Event;
 class ExceptionState;
@@ -62,6 +63,7 @@ class HTMLMediaSource;
 class TextTrackList;
 class TimeRanges;
 class URLRegistry;
+class VideoTrackList;
 
 typedef PODIntervalTree<double, TextTrackCue*> CueIntervalTree;
 typedef CueIntervalTree::IntervalType CueInterval;
@@ -163,6 +165,12 @@ public:
 
     virtual bool canPlay() const OVERRIDE FINAL;
 
+    AudioTrackList& audioTracks();
+    void audioTrackChanged(const AtomicString& audioTrackID, bool enabled);
+
+    VideoTrackList& videoTracks();
+    void selectedVideoTrackChanged(const AtomicString& selectedTrackID);
+
     PassRefPtr<TextTrack> addTextTrack(const AtomicString& kind, const AtomicString& label, const AtomicString& language, ExceptionState&);
     PassRefPtr<TextTrack> addTextTrack(const AtomicString& kind, const AtomicString& label, ExceptionState& exceptionState) { return addTextTrack(kind, label, emptyAtom, exceptionState); }
     PassRefPtr<TextTrack> addTextTrack(const AtomicString& kind, ExceptionState& exceptionState) { return addTextTrack(kind, emptyAtom, emptyAtom, exceptionState); }
@@ -181,6 +189,11 @@ public:
     void didAddTrackElement(HTMLTrackElement*);
     void didRemoveTrackElement(HTMLTrackElement*);
 
+    void addVideoTrack(const AtomicString& id, blink::WebMediaPlayerClient::VideoTrackKind, const AtomicString& label, const AtomicString& language, bool selected);
+    void removeVideoTrack(const AtomicString& id);
+    void addAudioTrack(const AtomicString& id, blink::WebMediaPlayerClient::AudioTrackKind, const AtomicString& label, const AtomicString& language, bool enabled);
+    void removeAudioTrack(const AtomicString& id);
+
     virtual void mediaPlayerDidAddTextTrack(blink::WebInbandTextTrack*) OVERRIDE FINAL;
     virtual void mediaPlayerDidRemoveTextTrack(blink::WebInbandTextTrack*) OVERRIDE FINAL;
     // FIXME: Remove this when WebMediaPlayerClientImpl::loadInternal does not depend on it.
@@ -417,6 +430,16 @@ private:
     bool isBlockedOnMediaController() const;
     bool isAutoplaying() const { return m_autoplaying; }
 
+    // Creates placeholder AudioTrack and/or VideoTrack objects when WebMemediaPlayer objects
+    // advertise they have audio and/or video, but don't explicity signal them via
+    // mediaPlayerDidAddAudioTrack() and mediaPlayerDidAddVideoTrack().
+    // FIXME: Remove this once all WebMediaPlayer implementations properly report their track info.
+    void createPlaceholderTracksIfNecessary();
+
+    // Sets the selected/enabled tracks if they aren't set before we initially
+    // transition to HAVE_METADATA.
+    void selectInitialTracksIfNecessary();
+
     Timer<HTMLMediaElement> m_loadTimer;
     Timer<HTMLMediaElement> m_progressEventTimer;
     Timer<HTMLMediaElement> m_playbackProgressTimer;
@@ -501,6 +524,8 @@ private:
     bool m_processingPreferenceChange : 1;
     double m_lastTextTrackUpdateTime;
 
+    RefPtr<AudioTrackList> m_audioTracks;
+    RefPtr<VideoTrackList> m_videoTracks;
     RefPtr<TextTrackList> m_textTracks;
     Vector<RefPtr<TextTrack> > m_textTracksWhenResourceSelectionBegan;