Fix app_shell shutdown crash due to BrowserContextKeyedServices

chrome/browser/chromeos/drive/drive_integration_service.cc

 // 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.
 
 #include "chrome/browser/chromeos/drive/drive_integration_service.h"
 
 #include "base/bind.h"
 #include "base/file_util.h"
 #include "base/prefs/pref_change_registrar.h"
 #include "base/prefs/pref_service.h"
@@ skipping 522 matching lines @@
   if (util::IsUnderDriveMountPoint(
           pref_service->GetFilePath(prefs::kDownloadDefaultDirectory))) {
     pref_service->SetFilePath(
         prefs::kDownloadDefaultDirectory,
         file_manager::util::GetDownloadsFolderForProfile(profile_));
   }
 }
 
 //===================== DriveIntegrationServiceFactory =======================
 
+DriveIntegrationServiceFactory::FactoryCallback*
+    DriveIntegrationServiceFactory::factory_for_test_ = NULL;
+
+DriveIntegrationServiceFactory::ScopedFactoryForTest::ScopedFactoryForTest(
+    FactoryCallback* factory_for_test) {
+  factory_for_test_ = factory_for_test;
+}
+
+DriveIntegrationServiceFactory::ScopedFactoryForTest::~ScopedFactoryForTest() {
+  factory_for_test_ = NULL;
+}
+
 // static
 DriveIntegrationService* DriveIntegrationServiceFactory::GetForProfile(
     Profile* profile) {
   return GetForProfileRegardlessOfStates(profile);
 }
 
 // static
 DriveIntegrationService*
 DriveIntegrationServiceFactory::GetForProfileRegardlessOfStates(
     Profile* profile) {
@@ skipping 13 matching lines @@
     Profile* profile) {
   return static_cast<DriveIntegrationService*>(
       GetInstance()->GetServiceForBrowserContext(profile, false));
 }
 
 // static
 DriveIntegrationServiceFactory* DriveIntegrationServiceFactory::GetInstance() {
   return Singleton<DriveIntegrationServiceFactory>::get();
 }
 
-// static
-void DriveIntegrationServiceFactory::SetFactoryForTest(
-    const FactoryCallback& factory_for_test) {
-  GetInstance()->factory_for_test_ = factory_for_test;
-}
-
 DriveIntegrationServiceFactory::DriveIntegrationServiceFactory()
     : BrowserContextKeyedServiceFactory(
         "DriveIntegrationService",
         BrowserContextDependencyManager::GetInstance()) {
   DependsOn(ProfileOAuth2TokenServiceFactory::GetInstance());
   DependsOn(DriveNotificationManagerFactory::GetInstance());
   DependsOn(DownloadServiceFactory::GetInstance());
 }
 
 DriveIntegrationServiceFactory::~DriveIntegrationServiceFactory() {
 }
 
 BrowserContextKeyedService*
 DriveIntegrationServiceFactory::BuildServiceInstanceFor(
     content::BrowserContext* context) const {
   Profile* profile = Profile::FromBrowserContext(context);
 
   DriveIntegrationService* service = NULL;
-  if (factory_for_test_.is_null()) {
+  if (!factory_for_test_) {
     DriveIntegrationService::PreferenceWatcher* preference_watcher = NULL;
     if (chromeos::IsProfileAssociatedWithGaiaAccount(profile)) {
       // Drive File System can be enabled.
       preference_watcher =
           new DriveIntegrationService::PreferenceWatcher(profile->GetPrefs());
     }
 
     service = new DriveIntegrationService(profile, preference_watcher,
                                           NULL, base::FilePath(), NULL);
   } else {
-    service = factory_for_test_.Run(profile);
+    service = factory_for_test_->Run(profile);
   }
 
   return service;
 }
 
 }  // namespace drive