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

services/media/factory_service/BUILD.gn

 # 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.
 
 import("//mojo/public/mojo_application.gni")
 import("//mojo/public/tools/bindings/mojom.gni")
 
 group("factory_service") {
   deps = [
     ":media_factory",
   ]
 }
 
 mojo_native_application("media_factory") {
   sources = [
-    "audio_track_controller.cc",
-    "audio_track_controller.h",
     "factory_service.cc",
     "factory_service.h",
     "main.cc",
     "media_decoder_impl.cc",
     "media_decoder_impl.h",
     "media_demux_impl.cc",
     "media_demux_impl.h",
     "media_player_impl.cc",
     "media_player_impl.h",
     "media_sink_impl.cc",
@@ skipping 20 matching lines @@
     "//mojo/services/network/interfaces",
     "//services/media/common",
     "//services/media/framework",
     "//services/media/framework_create",
     "//services/media/framework_ffmpeg",
     "//services/media/framework_mojo",
     "//services/util/cpp",
     "//url",
   ]
 }