Re-enable preferences service access for browser+ash

chrome/test/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/chrome_build.gni")
 import("//build/config/compiler/compiler.gni")
 import("//build/config/crypto.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//chrome/common/features.gni")
@@ skipping 2366 matching lines @@
         "../browser/ui/views/sync/profile_signin_confirmation_dialog_views_browsertest.cc",
         "../browser/ui/webui/signin/inline_login_ui_browsertest.cc",
 
         # chromeos does not use the desktop user manager
         "../browser/ui/webui/signin/user_manager_ui_browsertest.cc",
       ]
       deps += [
         "//chrome/browser/chromeos:arc_test_support",
         "//chromeos/ime:gencode",
         "//components/arc:arc_test_support",
+        "//components/prefs",
         "//components/user_manager:test_support",
+        "//services/preferences/public/cpp",
+        "//services/preferences/public/interfaces",
+        "//services/service_manager/public/cpp",
         "//ui/login:resources",
       ]
 
       if (use_dbus) {
         deps += [ "//dbus:test_support" ]
       }
     } else {  # !is_chromeos
       sources -= [
         "../browser/extensions/api/enterprise_device_attributes/enterprise_device_attributes_apitest.cc",
         "../browser/extensions/api/enterprise_platform_keys/enterprise_platform_keys_apitest_nss.cc",
@@ skipping 2786 matching lines @@
 }
 
 if (is_win) {
   loadable_module("conflicts_dll") {
     testonly = true
     sources = [
       "conflicts/conflicts_dll.cc",
     ]
   }
 }