Add SourceBuffer implementations of Audio/VideoTracks

third_party/WebKit/Source/modules/mediasource/AudioTrackSourceBuffer.cpp

Index: third_party/WebKit/Source/modules/mediasource/AudioTrackSourceBuffer.cpp
diff --git a/third_party/WebKit/Source/modules/mediasource/AudioTrackSourceBuffer.cpp b/third_party/WebKit/Source/modules/mediasource/AudioTrackSourceBuffer.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..3580fc33b1f4347057f2a6736e68e0f257926e19
--- /dev/null
+++ b/third_party/WebKit/Source/modules/mediasource/AudioTrackSourceBuffer.cpp
@@ -0,0 +1,16 @@
+// Copyright 2016 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 "modules/mediasource/AudioTrackSourceBuffer.h"
+
+#include "core/html/track/AudioTrack.h"
+
+namespace blink {
+
+AudioTrackSourceBuffer::AudioTrackSourceBuffer(AudioTrack& track, SourceBuffer* sourceBuffer)
+    : SourceBufferTrackBaseSupplement(track, sourceBuffer)
+{
+}
+
+} // namespace blink