Initialize DBus in mojo:ash on chrome os

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")
 
@@ skipping 86 matching lines @@
     "//ui/display/mojo",
     "//ui/events",
     "//ui/gfx",
     "//ui/gfx/geometry",
     "//ui/gfx/geometry/mojo",
     "//ui/resources",
     "//ui/strings",
     "//ui/views",
     "//ui/views/mus:for_mojo_application",
   ]
+
+  if (is_chromeos) {
+    deps += [ "//chromeos" ]
+  }
 }
 
 mojo_native_application("mus") {
   output_name = "ash"
 
   sources = [
     "main.cc",
   ]
 
   deps = [
@@ skipping 79 matching lines @@
     "//ui/gfx/geometry",
     "//ui/gfx/geometry/mojo",
     "//ui/views/mus",
   ]
 
   data_deps = [
     ":mus",
     "//mash/quick_launch",
   ]
 }