Add mojo interface+impl for audio stream control.

media/audio/BUILD.gn

 # Copyright 2014 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("//build/config/linux/pkg_config.gni")
 import("//media/media_options.gni")
 
 # When libpulse is not directly linked, use stubs to allow for dlopening of the
 # binary.
 if (!link_pulseaudio) {
@@ skipping 63 matching lines @@
     "audio_input_device.h",
     "audio_input_ipc.cc",
     "audio_input_ipc.h",
     "audio_io.h",
     "audio_manager.cc",
     "audio_manager.h",
     "audio_manager_base.cc",
     "audio_manager_base.h",
     "audio_output_controller.cc",
     "audio_output_controller.h",
+    "audio_output_delegate.cc",
+    "audio_output_delegate.h",
     "audio_output_device.cc",
     "audio_output_device.h",
     "audio_output_dispatcher.cc",
     "audio_output_dispatcher.h",
     "audio_output_dispatcher_impl.cc",
     "audio_output_dispatcher_impl.h",
     "audio_output_ipc.cc",
     "audio_output_ipc.h",
     "audio_output_proxy.cc",
     "audio_output_proxy.h",
@@ skipping 291 matching lines @@
     ]
   }
 
   if (use_alsa) {
     sources += [
       "alsa/alsa_output_unittest.cc",
       "audio_low_latency_input_output_unittest.cc",
     ]
   }
 }