Motown: Define MediaRenderer and make it the way we identify renderers.

mojo/services/media/core/interfaces/media_renderer.mojom

-// Copyright 2015 The Chromium Authors. All rights reserved.
+// 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.
 
 [DartPackage="mojo_services"]
 module mojo.media;
 
 import "mojo/services/media/common/interfaces/media_transport.mojom";
+import "mojo/services/media/common/interfaces/media_types.mojom";
 import "mojo/services/media/core/interfaces/timeline_controller.mojom";
 
-// TODO(dalesat): Define a media sink that multiplexes streams.
+// Models a service that renders content.
+interface MediaRenderer {
+  // Gets the list of supported media types.
+  GetSupportedMediaTypes() => (array<MediaTypeSet> supported_media_types);
 
-// Consumes media streams and delivers them to specified destinations.
-interface MediaSink {
-  // TODO(dalesat): Support fanout to many destinations.
+  // Sets the media type of the stream to be delivered.
+  SetMediaType(MediaType media_type);
 
   // Gets the consumer for the stream to be delivered.
   GetConsumer(MediaConsumer& consumer);
 
-  // Request the timeline control site for this sink
+  // Requests the timeline control site for this output.
   GetTimelineControlSite(MediaTimelineControlSite& timeline_control_site);
 };