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

Source/core/html/track/VideoTrackList.cpp

Index: Source/core/html/track/VideoTrackList.cpp
diff --git a/Source/core/html/track/VideoTrackList.cpp b/Source/core/html/track/VideoTrackList.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..0c3b210684ba0bd11330136c78b5af2b0f312335
--- /dev/null
+++ b/Source/core/html/track/VideoTrackList.cpp
@@ -0,0 +1,68 @@
+// 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 {
+
+VideoTrackList::~VideoTrackList()
+{
+}
+
+VideoTrackList::VideoTrackList(HTMLMediaElement* owner)
+    : TrackBaseList(owner)
+    , m_selectedIndex(-1)
+{
+    ScriptWrappable::init(this);
+}
+
+VideoTrack* VideoTrackList::anonymousIndexedGetter(unsigned index) const
+{
+    return static_cast<VideoTrack*>(getByIndex(index));
+}
+
+VideoTrack* VideoTrackList::getTrackById(const AtomicString& id) const
+{
+    return static_cast<VideoTrack*>(getById(id));
+}
+
+const AtomicString& VideoTrackList::interfaceName() const
+{
+    return EventTargetNames::VideoTrackList;
+}
+
+ExecutionContext* VideoTrackList::executionContext() const
+{
+    return owner()->executionContext();

[fs, 2014/02/24 10:32:36]

See comment in AudioTrackList::executionContext().

[acolwell GONE FROM CHROMIUM, 2014/03/07 22:08:43]

Done.

+}
+
+void VideoTrackList::trackSelected(VideoTrack* track)
+{
+    AtomicString oldTrackID;
+    AtomicString newTrackID;
+
+    if (m_selectedIndex != -1) {
+        VideoTrack* oldSelectedTrack = anonymousIndexedGetter(m_selectedIndex);
+        oldSelectedTrack->clearSelected();
+        oldTrackID = oldSelectedTrack->id();
+    }
+
+    if (track) {
+        m_selectedIndex = getIndex(track);
+        newTrackID = track->id();
+    } else {
+        m_selectedIndex = -1;
+    }
+
+    if (owner())
+        owner()->didSelectedVideoTrackChange(oldTrackID, newTrackID);
+
+    scheduleChangeEvent();
+}
+
+}