Add RetainedRef uses where needed.

chrome/browser/media_galleries/fileapi/native_media_file_util.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/media_galleries/fileapi/native_media_file_util.h"
 
 #include <string>
 #include <utility>
 
 #include "base/bind.h"
@@ skipping 117 matching lines @@
   if (file_flags & ~(base::File::FLAG_OPEN |
                      base::File::FLAG_READ |
                      base::File::FLAG_WRITE_ATTRIBUTES)) {
     callback.Run(base::File(base::File::FILE_ERROR_SECURITY), base::Closure());
     return;
   }
   scoped_refptr<base::SequencedTaskRunner> task_runner = context->task_runner();
   CreateSnapshotFile(
       std::move(context), url,
       base::Bind(&NativeMediaFileUtil::CreatedSnapshotFileForCreateOrOpen,
-                 task_runner, file_flags, callback));
+                 base::RetainedRef(task_runner), file_flags, callback));
 }
 
 void NativeMediaFileUtil::EnsureFileExists(
     scoped_ptr<storage::FileSystemOperationContext> context,
     const storage::FileSystemURL& url,
     const EnsureFileExistsCallback& callback) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
   callback.Run(base::File::FILE_ERROR_SECURITY, false);
 }
 
@@ skipping 519 matching lines @@
     return base::File::FILE_ERROR_FAILED;
 
   if (!file_info.is_directory &&
       !media_path_filter_->Match(file_path)) {
     return failure_error;
   }
 
   *local_file_path = file_path;
   return base::File::FILE_OK;
 }