Split ExtensionSystem interface from ExtensionSystemImpl implementation, part 1.

chrome/browser/sync_file_system/drive_backend/sync_engine.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/sync_file_system/drive_backend/sync_engine.h"
 
 #include "base/bind.h"
 #include "base/threading/sequenced_worker_pool.h"
 #include "base/values.h"
 #include "chrome/browser/drive/drive_api_service.h"
@@ skipping 64 matching lines @@
           base_drive_url, base_download_url, wapi_base_url,
           std::string() /* custom_user_agent */));
   drive_service->Initialize(token_service->GetPrimaryAccountId());
 
   scoped_ptr<drive::DriveUploaderInterface> drive_uploader(
       new drive::DriveUploader(drive_service.get(), drive_task_runner.get()));
 
   drive::DriveNotificationManager* notification_manager =
       drive::DriveNotificationManagerFactory::GetForBrowserContext(context);
   ExtensionService* extension_service =
-      extensions::ExtensionSystem::GetForBrowserContext(
+      extensions::ExtensionSystem::Get(
           context)->extension_service();
 
   scoped_refptr<base::SequencedTaskRunner> task_runner(
       worker_pool->GetSequencedTaskRunnerWithShutdownBehavior(
           worker_pool->GetSequenceToken(),
           base::SequencedWorkerPool::SKIP_ON_SHUTDOWN));
 
   scoped_ptr<drive_backend::SyncEngine> sync_engine(
       new SyncEngine(
           GetSyncFileSystemDir(context->GetPath()),
@@ skipping 602 matching lines @@
         tracker.tracker_kind() == TRACKER_KIND_APP_ROOT;
     if (is_app_enabled && !is_app_root_tracker_enabled)
       EnableOrigin(origin, base::Bind(&EmptyStatusCallback));
     else if (!is_app_enabled && is_app_root_tracker_enabled)
       DisableOrigin(origin, base::Bind(&EmptyStatusCallback));
   }
 }
 
 }  // namespace drive_backend
 }  // namespace sync_file_system