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

Source/core/html/track/AudioTrackList.h

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef AudioTrackList_h
+#define AudioTrackList_h
+
+#include "bindings/v8/ScriptWrappable.h"
+#include "core/html/track/TrackBaseList.h"
+
+namespace WebCore {
+
+class AudioTrack;
+class HTMLMediaElement;
+
+class AudioTrackList : public TrackBaseList, public ScriptWrappable {
+public:
+    static PassRefPtr<AudioTrackList> create(HTMLMediaElement* owner)
+    {
+        return adoptRef(new AudioTrackList(owner));
+    }
+    virtual ~AudioTrackList();
+
+    AudioTrack* anonymousIndexedGetter(unsigned index) const;
+    AudioTrack* getTrackById(const AtomicString& id) const;
+
+    bool hasEnabledTrack() const;
+
+    // EventTarget
+    virtual const AtomicString& interfaceName() const OVERRIDE;
+    virtual ExecutionContext* executionContext() const OVERRIDE;
+
+    void trackEnabled(const AtomicString& id, bool enabled);
+
+private:
+    AudioTrackList(HTMLMediaElement* owner);
+};
+
+}
+
+#endif