[Win] Unbreak the user manager tuturial that I broke in r259326.

chrome/browser/profiles/profile_window.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/profile_window.h"
 
 #include "base/command_line.h"
 #include "base/files/file_path.h"
 #include "base/prefs/pref_service.h"
 #include "base/strings/string_number_conversions.h"
@@ skipping 253 matching lines @@
       base::Bind(&OnUserManagerGuestProfileCreated,
                  profile_path_to_focus,
                  tutorial_mode,
                  callback),
       base::string16(),
       base::string16(),
       std::string());
 }
 
 void ShowUserManagerMaybeWithTutorial(Profile* profile) {
-  if (!profile) {
+  // Guest users cannot appear in the User Manager, nor display a tutorial.
+  if (!profile || profile->IsGuestSession()) {
     chrome::ShowUserManager(base::FilePath());
     return;
   }
   // Show the tutorial if the profile has not shown it before.
   PrefService* pref_service = profile->GetPrefs();
   bool tutorial_shown = pref_service->GetBoolean(
       prefs::kProfileUserManagerTutorialShown);
   if (!tutorial_shown)
     pref_service->SetBoolean(prefs::kProfileUserManagerTutorialShown, true);
 
   if (tutorial_shown) {
     chrome::ShowUserManager(profile->GetPath());
   } else {
     chrome::ShowUserManagerWithTutorial(
         profiles::USER_MANAGER_TUTORIAL_OVERVIEW);
   }
 }
 
 }  // namespace profiles