Implement AudioTrack, AudioTrackList, VideoTrack, and VideoTrackList

Source/core/html/track/AudioTrack.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 AudioTrack_h
+#define AudioTrack_h
+
+#include "bindings/v8/ScriptWrappable.h"
+#include "core/html/track/TrackBase.h"
+
+namespace WebCore {
+
+class HTMLMediaElement;
+
+class AudioTrack FINAL : public TrackBase, public ScriptWrappable {
+public:
+    static PassRefPtrWillBeRawPtr<AudioTrack> create(const String& id, const AtomicString& kind, const AtomicString& label, const AtomicString& language)
+    {
+        return adoptRefWillBeRefCountedGarbageCollected(new AudioTrack(id, kind, label, language));

[haraken, 2014/06/12 01:22:07]

Now that EventTarget is GarbageCollectedFinalized, you don't need to use
RefCountedGarbageCollected. So this can be adoptRefWillBeNoop.

+    }
+    virtual ~AudioTrack();
+
+    bool enabled() const { return m_enabled; }
+    void setEnabled(bool);
+
+    // Valid kind keywords.
+    static const AtomicString& alternativeKeyword();
+    static const AtomicString& descriptionsKeyword();
+    static const AtomicString& mainKeyword();
+    static const AtomicString& mainDescriptionsKeyword();
+    static const AtomicString& translationKeyword();
+    static const AtomicString& commentaryKeyword();
+
+private:
+    AudioTrack(const String& id, const AtomicString& kind, const AtomicString& label, const AtomicString& language);
+
+    // TrackBase
+    virtual bool isValidKind(const AtomicString&) const OVERRIDE;
+    virtual AtomicString defaultKind() const OVERRIDE;
+
+    bool m_enabled;
+};
+
+}
+
+#endif