[Sync] Register USS types with ModelTypeRegistry before download

components/sync_driver/non_blocking_data_type_controller.h

Index: components/sync_driver/non_blocking_data_type_controller.h
diff --git a/components/sync_driver/non_blocking_data_type_controller.h b/components/sync_driver/non_blocking_data_type_controller.h
index 3bb13d9cce81e923211dd0bb949b45523e1a9053..160b19144257790d8eb87e3133cb7e17a8aee2c1 100644
--- a/components/sync_driver/non_blocking_data_type_controller.h
+++ b/components/sync_driver/non_blocking_data_type_controller.h
@@ -49,6 +49,12 @@ class NonBlockingDataTypeController : public sync_driver::DataTypeController {
   // DataTypeController interface.
   bool ShouldLoadModelBeforeConfigure() const override;
   void LoadModels(const ModelLoadCallback& model_load_callback) override;
+
+  // Registers non-blocking data type with sync backend. In the process

[maxbogue, 2016/04/01 22:43:14]

In the process the

[pavely, 2016/04/04 17:57:16]

Done.

+  // activation context is passed to ModelTypeRegistry, ModelTypeWorker gets

[maxbogue, 2016/04/01 22:43:14]

"ModelTypeRegistry, ModelTypeWorker" -> "ModelTypeRegistry, where
ModelTypeWorker"

[pavely, 2016/04/04 17:57:16]

Done.

+  // created and connected with ModelTypeProcessor.
+  void RegisterWithBackend(
+      sync_driver::BackendDataTypeConfigurer* configurer) override;
   void StartAssociating(const StartCallback& start_callback) override;
   void ActivateDataType(
       sync_driver::BackendDataTypeConfigurer* configurer) override;