Loading the Launcher with a Locked Profile launched UserManager.

chrome/browser/ui/app_list/profile_loader.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/ui/app_list/profile_loader.h"
 
 #include "base/bind.h"
 #include "base/files/file_path.h"
 #include "chrome/browser/apps/scoped_keep_alive.h"
 #include "chrome/browser/ui/app_list/profile_store.h"
+#include "chrome/browser/ui/user_manager.h"
 
 ProfileLoader::ProfileLoader(ProfileStore* profile_store)
     : profile_store_(profile_store),
       profile_load_sequence_id_(0),
       pending_profile_loads_(0),
       weak_factory_(this) {
 }
 
 ProfileLoader::~ProfileLoader() {
 }
 
 bool ProfileLoader::IsAnyProfileLoading() const {
   return pending_profile_loads_ > 0;
 }
 
 void ProfileLoader::InvalidatePendingProfileLoads() {
   ++profile_load_sequence_id_;
 }
 
 void ProfileLoader::LoadProfileInvalidatingOtherLoads(
     const base::FilePath& profile_file_path,
     base::Callback<void(Profile*)> callback) {
   InvalidatePendingProfileLoads();
 
+  if (profile_store_->IsProfileLocked(profile_file_path)) {
+      UserManager::Show(base::FilePath(),
+                        profiles::USER_MANAGER_NO_TUTORIAL,
+                        profiles::USER_MANAGER_SELECT_PROFILE_APP_LAUNCHER);
+      return;
+  }
+
   Profile* profile = profile_store_->GetProfileByPath(profile_file_path);
   if (profile) {
     callback.Run(profile);
     return;
   }
 
   IncrementPendingProfileLoads();
   profile_store_->LoadProfileAsync(
       profile_file_path,
       base::Bind(&ProfileLoader::OnProfileLoaded,
@@ skipping 14 matching lines @@
   pending_profile_loads_++;
   if (pending_profile_loads_ == 1)
     keep_alive_.reset(new ScopedKeepAlive);
 }
 
 void ProfileLoader::DecrementPendingProfileLoads() {
   pending_profile_loads_--;
   if (pending_profile_loads_ == 0)
     keep_alive_.reset();
 }