chrome: Cleanup class/struct forward declarations

chrome/browser/signin/signin_ui_util.h

 // Copyright (c) 2013 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.
 
 #ifndef CHROME_BROWSER_SIGNIN_SIGNIN_UI_UTIL_H_
 #define CHROME_BROWSER_SIGNIN_SIGNIN_UI_UTIL_H_
 
 #include <string>
 #include <vector>
 
 #include "base/strings/string16.h"
 
-class GlobalError;
 class Profile;
 class SigninManagerBase;
 
 // Utility functions to gather status information from the various signed in
 // services and construct messages suitable for showing in UI.
 namespace signin_ui_util {
 
 // The maximum number of times to show the welcome tutorial for an upgrade user.
 const int kUpgradeWelcomeTutorialShowMax = 1;
 
 // Returns the username of the authenticated user or an empty string if there is
 // no authenticated user.
 base::string16 GetAuthenticatedUsername(const SigninManagerBase* signin);
 
 // Initializes signin-related preferences.
 void InitializePrefsForProfile(Profile* profile);
 
 // Shows a learn more page for signin errors.
 void ShowSigninErrorLearnMorePage(Profile* profile);
 
 // Returns the display email string for the given account.  If the profile
 // has not been migrated to use gaia ids, then its possible for the display
 // to not ne known yet.  In this case, use |account_id|, which is assumed to
 // be an email address.
 std::string GetDisplayEmail(Profile* profile, const std::string& account_id);
 
 }  // namespace signin_ui_util
 
 #endif  // CHROME_BROWSER_SIGNIN_SIGNIN_UI_UTIL_H_