[SyncFS] Initialize SyncEngine::remote_change_processor_ in the constructor

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 <vector>
 
 #include "base/bind.h"
 #include "base/metrics/histogram.h"
@@ skipping 562 matching lines @@
     : ui_task_runner_(ui_task_runner),
       worker_task_runner_(worker_task_runner),
       file_task_runner_(file_task_runner),
       drive_task_runner_(drive_task_runner),
       task_logger_(task_logger),
       notification_manager_(notification_manager),
       extension_service_(extension_service),
       signin_manager_(signin_manager),
       token_service_(token_service),
       request_context_(request_context),
+      remote_change_processor_(NULL),
       service_state_(REMOTE_SERVICE_TEMPORARY_UNAVAILABLE),
       sync_enabled_(false),
       env_override_(env_override),
       weak_ptr_factory_(this) {}
 
 void SyncEngine::OnPendingFileListUpdated(int item_count) {
   FOR_EACH_OBSERVER(
       Observer,
       service_observers_,
       OnRemoteChangeQueueUpdated(item_count));
@@ skipping 20 matching lines @@
 
 SyncStatusCallback SyncEngine::TrackCallback(
     const SyncStatusCallback& callback) {
   return callback_tracker_.Register(
       base::Bind(callback, SYNC_STATUS_ABORT),
       callback);
 }
 
 }  // namespace drive_backend
 }  // namespace sync_file_system