Replace direct access to kGoogleServicesUsername with calls to SigninManager.

chrome/browser/ui/webui/options/chromeos/accounts_options_browsertest.cc

 // 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.
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/prefs/pref_service.h"
 #include "chrome/browser/chromeos/login/login_manager_test.h"
 #include "chrome/browser/chromeos/login/startup_utils.h"
 #include "chrome/browser/chromeos/login/ui/user_adding_screen.h"
@@ skipping 45 matching lines @@
     LoginManagerTest::TearDownOnMainThread();
   }
 
   virtual void SetUpCommandLine(CommandLine* command_line) override {
     LoginManagerTest::SetUpCommandLine(command_line);
   }
 
  protected:
   void CheckAccountsUI(const user_manager::User* user, bool is_owner) {
     Profile* profile = ProfileHelper::Get()->GetProfileByUserUnsafe(user);
-    profile->GetPrefs()->SetString(prefs::kGoogleServicesUsername,
-                                   user->email());
 
     ui_test_utils::BrowserAddedObserver observer;
     Browser* browser = CreateBrowser(profile);
     observer.WaitForSingleNewBrowser();
 
     ui_test_utils::NavigateToURL(browser,
                                  GURL("chrome://settings-frame/accounts"));
     content::WebContents* contents =
         browser->tab_strip_model()->GetActiveWebContents();
 
@@ skipping 59 matching lines @@
   AddUser(kTestUsers[1]);
 
   user_manager::UserManager* manager = user_manager::UserManager::Get();
   ASSERT_EQ(2u, manager->GetLoggedInUsers().size());
 
   CheckAccountsUI(manager->FindUser(kTestUsers[0]), true /* is_owner */);
   CheckAccountsUI(manager->FindUser(kTestUsers[1]), false /* is_owner */);
 }
 
 }  // namespace chromeos