Remove TrayAudioDelegate

ash/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/features.gni")
 import("//build/config/ui.gni")
 import("//testing/test.gni")
 import("//ui/base/ui_features.gni")
 
 # Historical note: Ash shipped on Windows for a couple years to support
@@ skipping 181 matching lines @@
     "common/shell_delegate.h",
     "common/shell_observer.h",
     "common/shutdown_controller.cc",
     "common/shutdown_controller.h",
     "common/system/accessibility_observer.h",
     "common/system/brightness_control_delegate.h",
     "common/system/chromeos/audio/audio_detailed_view.cc",
     "common/system/chromeos/audio/audio_detailed_view.h",
     "common/system/chromeos/audio/tray_audio.cc",
     "common/system/chromeos/audio/tray_audio.h",
-    "common/system/chromeos/audio/tray_audio_delegate.h",
-    "common/system/chromeos/audio/tray_audio_delegate_chromeos.cc",
-    "common/system/chromeos/audio/tray_audio_delegate_chromeos.h",
     "common/system/chromeos/audio/volume_view.cc",
     "common/system/chromeos/audio/volume_view.h",
     "common/system/chromeos/bluetooth/bluetooth_notification_controller.cc",
     "common/system/chromeos/bluetooth/bluetooth_notification_controller.h",
     "common/system/chromeos/bluetooth/bluetooth_observer.h",
     "common/system/chromeos/bluetooth/tray_bluetooth.cc",
     "common/system/chromeos/bluetooth/tray_bluetooth.h",
     "common/system/chromeos/bluetooth/tray_bluetooth_helper.cc",
     "common/system/chromeos/bluetooth/tray_bluetooth_helper.h",
     "common/system/chromeos/brightness/brightness_controller_chromeos.cc",
@@ skipping 1292 matching lines @@
     "//content/public/app:both",
     "//device/bluetooth",
   ]
 
   data_deps = [
     "//ash/strings:ash_test_strings",
     "//ash/resources:ash_test_resources_with_content_100_percent",
     "//ash/resources:ash_test_resources_200_percent",
   ]
 }