[Sync] DeviceInfoService static method and error cleanup.

components/sync/model/model_type_service.h

Index: components/sync/model/model_type_service.h
diff --git a/components/sync/model/model_type_service.h b/components/sync/model/model_type_service.h
index 3d39d5b16687db84b56f7ea3e3bf599baf34813c..a58b0b4313edbd7c7e311c0b04f6e08e3d4dbd30 100644
--- a/components/sync/model/model_type_service.h
+++ b/components/sync/model/model_type_service.h
@@ -26,7 +26,11 @@ class MetadataChangeList;
 
 // Interface implemented by model types to receive updates from sync via the
 // SharedModelTypeProcessor. Provides a way for sync to update the data and
-// metadata for entities, as well as the model type state.
+// metadata for entities, as well as the model type state. Service

[maxbogue, 2016/10/28 20:20:02]

s/Service/Sync bridge/

[skym, 2016/10/28 20:46:16]

Done.

+// implementations have the responsibility of providing thier change_processor()
+// with metadata through ModelTypeChangeProcessor::OnMetadataLoaded() as soon as
+// possible. Sync will wait for this method to be called, and afterwards it will
+// start calling into the service.

[maxbogue, 2016/10/28 20:20:02]

bridge

[skym, 2016/10/28 20:46:16]

Done.

 class ModelTypeService : public base::SupportsWeakPtr<ModelTypeService> {
  public:
   typedef base::Callback<void(SyncError, std::unique_ptr<DataBatch>)>