Add RetainedRef uses where needed.

chrome/browser/sync_file_system/local/sync_file_system_backend.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/local/sync_file_system_backend.h"
 
 #include <string>
 #include <utility>
 
 #include "base/logging.h"
@@ skipping 109 matching lines @@
                                   url.type(),
                                   mode,
                                   callback,
                                   GetSyncableFileSystemRootURI(url.origin()));
     return;
   }
 
   // It is safe to pass Unretained(this) since |context_| owns it.
   SyncStatusCallback initialize_callback =
       base::Bind(&SyncFileSystemBackend::DidInitializeSyncFileSystemService,
-                 base::Unretained(this),
-                 make_scoped_refptr(context_),
-                 url.origin(),
-                 url.type(),
-                 mode,
-                 callback);
+                 base::Unretained(this), base::RetainedRef(context_),
+                 url.origin(), url.type(), mode, callback);
   InitializeSyncFileSystemService(url.origin(), initialize_callback);
 }
 
 storage::AsyncFileUtil* SyncFileSystemBackend::GetAsyncFileUtil(
     storage::FileSystemType type) {
   return GetDelegate()->file_util();
 }
 
 storage::WatcherManager* SyncFileSystemBackend::GetWatcherManager(
     storage::FileSystemType type) {
@@ skipping 152 matching lines @@
     storage::OpenFileSystemMode mode,
     const OpenFileSystemCallback& callback,
     SyncStatusCode status) {
   // Repost to switch from UI thread to IO thread.
   if (!BrowserThread::CurrentlyOn(BrowserThread::IO)) {
     DCHECK_CURRENTLY_ON(BrowserThread::UI);
     // It is safe to pass Unretained(this) since |context| owns it.
     BrowserThread::PostTask(
         BrowserThread::IO, FROM_HERE,
         base::Bind(&SyncFileSystemBackend::DidInitializeSyncFileSystemService,
-                   base::Unretained(this), make_scoped_refptr(context),
+                   base::Unretained(this), base::RetainedRef(context),
                    origin_url, type, mode, callback, status));
     return;
   }
 
   if (status != sync_file_system::SYNC_STATUS_OK) {
     callback.Run(GURL(), std::string(),
                  SyncStatusCodeToFileError(status));
     return;
   }
 
   callback.Run(GetSyncableFileSystemRootURI(origin_url),
                GetFileSystemName(origin_url, type),
                base::File::FILE_OK);
 }
 
 }  // namespace sync_file_system