Implement MojoAudioRendererSink and use it in UtilityMojoMediaClient

media/mojo/interfaces/output_device_info.mojom

Index: media/mojo/interfaces/output_device_info.mojom
diff --git a/media/mojo/interfaces/output_device_info.mojom b/media/mojo/interfaces/output_device_info.mojom
new file mode 100644
index 0000000000000000000000000000000000000000..80445f58be4f973d42dcd2116673dc70a93f207f
--- /dev/null
+++ b/media/mojo/interfaces/output_device_info.mojom
@@ -0,0 +1,9 @@
+// Copyright 2017 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.
+
+module media.mojom;
+
+// Native struct media::OutputDeviceInfo;
+[Native]
+struct OutputDeviceInfo;