Add SourceBuffer implementations of Audio/VideoTracks

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

Index: third_party/WebKit/Source/modules/mediasource/AudioTrackSourceBuffer.idl
diff --git a/third_party/WebKit/Source/modules/mediasource/AudioTrackSourceBuffer.idl b/third_party/WebKit/Source/modules/mediasource/AudioTrackSourceBuffer.idl
new file mode 100644
index 0000000000000000000000000000000000000000..5ba84162b3cee55756a1e1daafee1519e4423eb8
--- /dev/null
+++ b/third_party/WebKit/Source/modules/mediasource/AudioTrackSourceBuffer.idl
@@ -0,0 +1,8 @@
+// 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.
+
+// https://w3c.github.io/media-source/#audio-track-extensions
+[RuntimeEnabled=AudioVideoTracks] partial interface AudioTrack {

[philipj_slow, 2016/02/26 13:36:54]

Please format like this:
[
    RuntimeEnabled=AudioVideoTracks,
] partial interface ...

That's the norm, probably because it makes diffs when adding/removing extended
attributes smaller. Also a blank line after the URL, at least I've done that
almost everywhere.

[servolk, 2016/03/03 03:39:26]

Done.

+    readonly attribute SourceBuffer? sourceBuffer;
+};