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

Source/core/html/track/VideoTrackList.cpp

+// 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.
+
+#include "config.h"
+#include "core/html/track/VideoTrackList.h"
+
+#include "core/html/HTMLMediaElement.h"
+#include "core/html/track/VideoTrack.h"
+
+namespace WebCore {
+
+PassRefPtr<VideoTrackList> VideoTrackList::create(HTMLMediaElement& mediaElement)
+{
+    return adoptRef(new VideoTrackList(mediaElement));
+}
+
+VideoTrackList::~VideoTrackList()
+{
+}
+
+VideoTrackList::VideoTrackList(HTMLMediaElement& mediaElement)
+    : TrackListBase<VideoTrack>(&mediaElement)
+    , m_selectedIndex(-1)
+{
+    ScriptWrappable::init(this);
+}
+
+const AtomicString& VideoTrackList::interfaceName() const
+{
+    return EventTargetNames::VideoTrackList;
+}
+
+void VideoTrackList::trackSelected(const String& selectedTrackID)
+{
+    bool scheduleEvent = false;
+    if (m_selectedIndex != -1) {
+        RefPtr<VideoTrack> oldTrack = anonymousIndexedGetter(m_selectedIndex);
+
+        ASSERT(oldTrack->id() != selectedTrackID);
+
+        oldTrack->clearSelected();
+        m_selectedIndex = -1;
+        scheduleEvent = true;
+    }
+
+    if (!selectedTrackID.isEmpty()) {
+        for (unsigned i = 0; i < length(); ++i) {
+            RefPtr<VideoTrack> track = anonymousIndexedGetter(i);
+
+            if (track->id() != selectedTrackID)
+                continue;
+
+            m_selectedIndex = i;
+            scheduleEvent = true;
+            break;
+        }
+    }
+
+    if (scheduleEvent)
+        scheduleChangeEvent();
+}
+
+}