Persist Directory to disk when the app is backgrounded.

chrome/browser/sync/glue/sync_backend_host_mock.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/glue/sync_backend_host_mock.h"
 
 #include "components/sync_driver/sync_frontend.h"
 
 namespace browser_sync {
 
@@ skipping 97 matching lines @@
   return false;
 }
 
 void SyncBackendHostMock::GetModelSafeRoutingInfo(
     syncer::ModelSafeRoutingInfo* out) const {}
 
 SyncedDeviceTracker* SyncBackendHostMock::GetSyncedDeviceTracker() const {
   return NULL;
 }
 
+void SyncBackendHostMock::FlushDirectory() const {}
+
 base::MessageLoop* SyncBackendHostMock::GetSyncLoopForTesting() {
   return NULL;
 }
 
 void SyncBackendHostMock::RequestBufferedProtocolEventsAndEnableForwarding() {}
 
 void SyncBackendHostMock::DisableProtocolEventForwarding() {}
 
 void SyncBackendHostMock::EnableDirectoryTypeDebugInfoForwarding() {}
 
 void SyncBackendHostMock::DisableDirectoryTypeDebugInfoForwarding() {}
 
 void SyncBackendHostMock::GetAllNodesForTypes(
     syncer::ModelTypeSet types,
     base::Callback<void(const std::vector<syncer::ModelType>& type,
                         ScopedVector<base::ListValue>) > callback) {}
 
 void SyncBackendHostMock::set_fail_initial_download(bool should_fail) {
   fail_initial_download_ = should_fail;
 }
 
 }  // namespace browser_sync