[USS] Change the place where SharedModelTypeProcessor got created

components/sync_driver/device_info_service.cc

 // Copyright 2015 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 "components/sync_driver/device_info_service.h"
 
 #include <set>
 #include <utility>
 #include <vector>
 
@@ skipping 24 matching lines @@
 using sync_pb::DeviceInfoSpecifics;
 using sync_pb::EntitySpecifics;
 
 using Record = ModelTypeStore::Record;
 using RecordList = ModelTypeStore::RecordList;
 using Result = ModelTypeStore::Result;
 using WriteBatch = ModelTypeStore::WriteBatch;
 
 DeviceInfoService::DeviceInfoService(
     sync_driver::LocalDeviceInfoProvider* local_device_info_provider,
-    const StoreFactoryFunction& callback)
-    : local_device_info_provider_(local_device_info_provider),
+    const StoreFactoryFunction& callback,
+    const ChangeProcessorFactory& change_processor_factory)
+    : ModelTypeService(change_processor_factory),
+      local_device_info_provider_(local_device_info_provider),
       weak_factory_(this) {
   DCHECK(local_device_info_provider);
 
   // This is not threadsafe, but presuably the provider initializes on the same
   // thread as us so we're okay.
   if (local_device_info_provider->GetLocalDeviceInfo()) {
     OnProviderInitialized();
   } else {
     subscription_ =
         local_device_info_provider->RegisterOnInitializedCallback(base::Bind(
@@ skipping 306 matching lines @@
     LOG(WARNING) << "Initial load of data failed.";
     // TODO(skym, crbug.com/582460): Handle unrecoverable initialization
     // failure.
   }
 }
 
 void DeviceInfoService::OnReadAllMetadata(
     Result result,
     scoped_ptr<RecordList> metadata_records,
     const std::string& global_metadata) {
+  if (metadata_records->size() > 0 || global_metadata.size() > 0) {
+    GetOrCreateChangeProcessor();
+  }
   if (!change_processor()) {
     // This datatype was disabled while this read was oustanding.
     return;
   }
   if (result != Result::SUCCESS) {
     // Store has encountered some serious error. We should still be able to
     // continue as a read only service, since if we got this far we must have
     // loaded all data out succesfully. TODO(skym): Should we communicate this
     // to sync somehow?
     LOG(WARNING) << "Load of metadata completely failed.";
@@ skipping 31 matching lines @@
     LOG(WARNING) << "Failed a write to store.";
   }
 }
 
 void DeviceInfoService::TryReconcileLocalAndStored() {
   // TODO(skym, crbug.com/582460): Implement logic to reconcile provider and
   // stored device infos.
 }
 
 void DeviceInfoService::TryLoadAllMetadata() {
-  if (has_data_loaded_ && change_processor()) {
+  // TODO(skym): fix the double load metadata issue

[skym, 2016/03/24 22:51:37]

nit: Comments should look like sentences with capital first letter and period at
the end. :P

[Gang Wu, 2016/03/25 02:07:00]

Done.

+  if (has_data_loaded_) {
     store_->ReadAllMetadata(base::Bind(&DeviceInfoService::OnReadAllMetadata,
                                        weak_factory_.GetWeakPtr()));
   }
 }
 
+syncer::ModelType DeviceInfoService::type() const {
+  return syncer::DEVICE_INFO;
+}
+
 }  // namespace sync_driver_v2