Move AccessibilityDelegate ownership to ash::WmShell

ash/mus/BUILD.gn

 # Copyright 2015 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/ui.gni")
 import("//mojo/public/mojo_application.gni")
 import("//mojo/public/mojo_application_manifest.gni")
 import("//mojo/public/tools/bindings/mojom.gni")
 import("//tools/grit/repack.gni")
 
 source_set("lib") {
   sources = [
     "accelerator_registrar_impl.cc",
     "accelerator_registrar_impl.h",
+    "accessibility_delegate_mus.cc",
+    "accessibility_delegate_mus.h",
     "bridge/mus_layout_manager_adapter.cc",
     "bridge/mus_layout_manager_adapter.h",
     "bridge/wm_lookup_mus.cc",
     "bridge/wm_lookup_mus.h",
     "bridge/wm_root_window_controller_mus.cc",
     "bridge/wm_root_window_controller_mus.h",
     "bridge/wm_shelf_mus.cc",
     "bridge/wm_shelf_mus.h",
     "bridge/wm_shell_mus.cc",
     "bridge/wm_shell_mus.h",
@@ skipping 178 matching lines @@
     "//ui/gfx/geometry",
     "//ui/gfx/geometry/mojo",
     "//ui/views/mus",
   ]
 
   data_deps = [
     ":mus",
     "//mash/quick_launch",
   ]
 }