Fix FakeSigninManager::SignOut

chrome/browser/signin/fake_signin_manager.cc

 // 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.
 
 #include "chrome/browser/signin/fake_signin_manager.h"
 
 #include "base/callback_helpers.h"
 #include "base/prefs/pref_service.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/signin/account_tracker_service_factory.h"
@@ skipping 71 matching lines @@
                     GoogleSigninFailed(error));
 }
 
 void FakeSigninManager::SignOut(
     signin_metrics::ProfileSignout signout_source_metric) {
   if (IsSignoutProhibited())
     return;
   set_auth_in_progress(std::string());
   set_password(std::string());
   const std::string account_id = GetAuthenticatedAccountId();
-  const std::string username = authenticated_username_;
-  authenticated_username_.clear();
+  const std::string username = GetAuthenticatedUsername();
+  ClearAuthenticatedUsername();
 
   FOR_EACH_OBSERVER(SigninManagerBase::Observer, observer_list_,
                     GoogleSignedOut(account_id, username));
 }
 
 #endif  // !defined (OS_CHROMEOS)