Change single-interface mojo bindings to use SequencedTaskRunner.

services/file/file_service.cc

 // Copyright 2016 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 "services/file/file_service.h"
 
 #include "base/bind.h"
 #include "base/memory/ptr_util.h"
 #include "base/memory/weak_ptr.h"
+#include "base/single_thread_task_runner.h"
 #include "components/filesystem/lock_table.h"
 #include "components/leveldb/leveldb_service_impl.h"
 #include "mojo/public/cpp/bindings/strong_binding.h"
 #include "services/file/file_system.h"
 #include "services/file/user_id_map.h"
 #include "services/service_manager/public/cpp/connection.h"
 #include "services/service_manager/public/cpp/interface_registry.h"
 #include "services/service_manager/public/cpp/service_context.h"
 
 namespace file {
@@ skipping 99 matching lines @@
                          leveldb::mojom::LevelDBServiceRequest request) {
   leveldb_service_runner_->PostTask(
       FROM_HERE,
       base::Bind(
           &FileService::LevelDBServiceObjects::OnLevelDBServiceRequest,
           leveldb_objects_->AsWeakPtr(), remote_identity,
           base::Passed(&request)));
 }
 
 }  // namespace user_service