[cros] Use mocked URLFetcher and other mocks in ExistingUserController tests.

chrome/chrome_browser.gypi

 # Copyright (c) 2012 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.
 
 {
   'targets': [
     {
       'target_name': 'browser',
       'type': 'static_library',
       'variables': { 'enable_wexit_time_destructors': 1, },
@@ skipping 684 matching lines @@
         'browser/chromeos/login/update_screen_actor.h',
         'browser/chromeos/login/user.cc',
         'browser/chromeos/login/user.h',
         'browser/chromeos/login/user_image_loader.cc',
         'browser/chromeos/login/user_image_loader.h',
         'browser/chromeos/login/user_image_screen.cc',
         'browser/chromeos/login/user_image_screen.h',
         'browser/chromeos/login/user_image_screen_actor.h',
         'browser/chromeos/login/user_manager.cc',
         'browser/chromeos/login/user_manager.h',
+        'browser/chromeos/login/user_manager_impl.cc',
+        'browser/chromeos/login/user_manager_impl.h',
         'browser/chromeos/login/username_view.cc',
         'browser/chromeos/login/username_view.h',
         'browser/chromeos/login/version_info_updater.cc',
         'browser/chromeos/login/version_info_updater.h',
         'browser/chromeos/login/view_screen.h',
         'browser/chromeos/login/web_page_screen.cc',
         'browser/chromeos/login/web_page_screen.h',
         'browser/chromeos/login/web_page_view.cc',
         'browser/chromeos/login/web_page_view.h',
         'browser/chromeos/login/webui_login_display.cc',
@@ skipping 4982 matching lines @@
          'variables': {
           'proto_in_dir': '../third_party/cros_system_api/dbus/',
           'proto_out_dir': 'chrome/browser/chromeos/dbus',
          },
          'includes': ['../build/protoc.gypi'],
         }],
       ],
     },
   ],
 }