The User Manager should be backed by a special profile, not the guest one.

chrome/browser/app_controller_mac_browsertest.mm

 // 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.
 
 #import <Cocoa/Cocoa.h>
 
 #include "apps/app_window_registry.h"
 #include "base/command_line.h"
 #include "base/mac/scoped_nsobject.h"
 #include "base/prefs/pref_service.h"
@@ skipping 116 matching lines @@
                            Profile::CreateStatus status) {
   EXPECT_TRUE(profile);
   EXPECT_NE(Profile::CREATE_STATUS_LOCAL_FAIL, status);
   EXPECT_NE(Profile::CREATE_STATUS_REMOTE_FAIL, status);
   // This will be called multiple times. Wait until the profile is initialized
   // fully to quit the loop.
   if (status == Profile::CREATE_STATUS_INITIALIZED)
     quit_closure.Run();
 }
 
-void CreateAndWaitForGuestProfile() {
+void CreateAndWaitForProfileWithPath(const base::FilePath& path) {
   ProfileManager::CreateCallback create_callback =
       base::Bind(&CreateProfileCallback,
                  base::MessageLoop::current()->QuitClosure());
   g_browser_process->profile_manager()->CreateProfileAsync(
-      ProfileManager::GetGuestProfilePath(),
+      path,
       create_callback,
       base::string16(),
       base::string16(),
       std::string());
   base::RunLoop().Run();
 }
 
 class AppControllerNewProfileManagementBrowserTest
     : public InProcessBrowserTest {
  protected:
@@ skipping 17 matching lines @@
   BOOL result = [ac applicationShouldHandleReopen:NSApp hasVisibleWindows:NO];
 
   EXPECT_FALSE(result);
   EXPECT_EQ(2u, active_browser_list_->size());
   EXPECT_FALSE(UserManagerMac::IsShowing());
 }
 
 // Test that for a locked last profile, a reopen event opens the User Manager.
 IN_PROC_BROWSER_TEST_F(AppControllerNewProfileManagementBrowserTest,
                        LockedProfileReopenWithNoWindows) {
-  // The User Manager uses the guest profile as its underlying profile. To
+  // The User Manager uses a special profile as its underlying profile. To
   // minimize flakiness due to the scheduling/descheduling of tasks on the
-  // different threads, pre-initialize the guest profile before it is needed.
-  CreateAndWaitForGuestProfile();
+  // different threads, pre-initialize this profile before it is needed.
+  CreateAndWaitForProfileWithPath(ProfileManager::GetUserManagerProfilePath());
   base::scoped_nsobject<AppController> ac([[AppController alloc] init]);
 
   // Lock the active profile.
   Profile* profile = [ac lastProfile];
   ProfileInfoCache& cache =
       g_browser_process->profile_manager()->GetProfileInfoCache();
   size_t profile_index = cache.GetIndexOfProfileWithPath(profile->GetPath());
   cache.SetProfileSigninRequiredAtIndex(profile_index, true);
   EXPECT_TRUE(cache.ProfileIsSigninRequiredAtIndex(profile_index));
 
   EXPECT_EQ(1u, active_browser_list_->size());
   BOOL result = [ac applicationShouldHandleReopen:NSApp hasVisibleWindows:NO];
   EXPECT_FALSE(result);
 
   base::RunLoop().RunUntilIdle();
   EXPECT_EQ(1u, active_browser_list_->size());
   EXPECT_TRUE(UserManagerMac::IsShowing());
   UserManagerMac::Hide();
 }
 
 // Test that for a guest last profile, a reopen event opens the User Manager.
 IN_PROC_BROWSER_TEST_F(AppControllerNewProfileManagementBrowserTest,
                        GuestProfileReopenWithNoWindows) {
   // Create the guest profile, and set it as the last used profile so the
   // app controller can use it on init.
-  CreateAndWaitForGuestProfile();
+  CreateAndWaitForProfileWithPath(ProfileManager::GetGuestProfilePath());
   PrefService* local_state = g_browser_process->local_state();
   local_state->SetString(prefs::kProfileLastUsed, chrome::kGuestProfileDir);
 
   base::scoped_nsobject<AppController> ac([[AppController alloc] init]);
 
   Profile* profile = [ac lastProfile];
   EXPECT_EQ(ProfileManager::GetGuestProfilePath(), profile->GetPath());
   EXPECT_TRUE(profile->IsGuestSession());
 
   EXPECT_EQ(1u, active_browser_list_->size());
   BOOL result = [ac applicationShouldHandleReopen:NSApp hasVisibleWindows:NO];
   EXPECT_FALSE(result);
 
   base::RunLoop().RunUntilIdle();
 
   EXPECT_EQ(1u, active_browser_list_->size());
   EXPECT_TRUE(UserManagerMac::IsShowing());
   UserManagerMac::Hide();
 }
 
 }  // namespace