Make sure auth error reporting handles guest mode correctly.

chrome/browser/profiles/profiles_state.cc

 // Copyright 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.
 
 #include "chrome/browser/profiles/profiles_state.h"
 
 #include "base/files/file_path.h"
 #include "base/prefs/pref_registry_simple.h"
 #include "base/prefs/pref_service.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 104 matching lines @@
 void UpdateGaiaProfilePhotoIfNeeded(Profile* profile) {
   // If the --google-profile-info flag isn't used, then the
   // GAIAInfoUpdateService isn't initialized, and we can't download the picture.
   if (!switches::IsGoogleProfileInfo())
     return;
 
   DCHECK(profile);
   GAIAInfoUpdateServiceFactory::GetInstance()->GetForProfile(profile)->Update();
 }
 
+SigninErrorController* GetSigninErrorController(Profile* profile) {
+  ProfileOAuth2TokenService* token_service =
+      ProfileOAuth2TokenServiceFactory::GetForProfile(profile);
+  return token_service ? token_service->signin_error_controller() : NULL;
+}
+
 }  // namespace profiles