Move FakeAttachmentStore from IO thread to FILE thread.

chrome/browser/sync/profile_sync_components_factory_impl.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 "base/command_line.h"
 #include "build/build_config.h"
 #include "chrome/browser/bookmarks/bookmark_model_factory.h"
 #include "chrome/browser/bookmarks/enhanced_bookmarks_features.h"
 #include "chrome/browser/dom_distiller/dom_distiller_service_factory.h"
 #include "chrome/browser/history/history_service.h"
@@ skipping 559 matching lines @@
 ProfileSyncComponentsFactoryImpl::CreateAttachmentService(
     syncer::AttachmentService::Delegate* delegate) {
   // TODO(maniscalco): Use a shared (one per profile) thread-safe instance of
   // AttachmentUpload instead of creating a new one per AttachmentService (bug
   // 369536).
   scoped_ptr<syncer::AttachmentUploader> attachment_uploader(
       new syncer::FakeAttachmentUploader);
 
   scoped_ptr<syncer::AttachmentStore> attachment_store(
       new syncer::FakeAttachmentStore(
-          BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO)));
+          BrowserThread::GetMessageLoopProxyForThread(BrowserThread::FILE)));
 
   scoped_ptr<syncer::AttachmentService> attachment_service(
       new syncer::AttachmentServiceImpl(
           attachment_store.Pass(), attachment_uploader.Pass(), delegate));
 
   return attachment_service.Pass();
 }
 
 ProfileSyncComponentsFactory::SyncComponents
     ProfileSyncComponentsFactoryImpl::CreateBookmarkSyncComponents(
@@ skipping 30 matching lines @@
       new TypedUrlModelAssociator(profile_sync_service,
                                   history_backend,
                                   error_handler);
   TypedUrlChangeProcessor* change_processor =
       new TypedUrlChangeProcessor(profile_,
                                   model_associator,
                                   history_backend,
                                   error_handler);
   return SyncComponents(model_associator, change_processor);
 }