Sync: Refactoring DataTypeController to make the design shareable with USS datatypes.

components/sync_driver/proxy_data_type_controller.cc

Index: components/sync_driver/proxy_data_type_controller.cc
diff --git a/components/sync_driver/proxy_data_type_controller.cc b/components/sync_driver/proxy_data_type_controller.cc
index e9b87326ffa8afd9730f669b2708de1537a47b80..8b4ca03db4641497ef60ba20057964e9ab6cf9b9 100644
--- a/components/sync_driver/proxy_data_type_controller.cc
+++ b/components/sync_driver/proxy_data_type_controller.cc
@@ -4,10 +4,12 @@
 
 #include "components/sync_driver/proxy_data_type_controller.h"
 
+#include "sync/api/sync_merge_result.h"
+
 namespace sync_driver {
 
 ProxyDataTypeController::ProxyDataTypeController(
-    scoped_refptr<base::SingleThreadTaskRunner> ui_thread,
+    const scoped_refptr<base::SingleThreadTaskRunner>& ui_thread,
     syncer::ModelType type)
     : DataTypeController(ui_thread, base::Closure()),
       state_(NOT_RUNNING),
@@ -43,15 +45,6 @@ syncer::ModelType ProxyDataTypeController::type() const {
   return type_;
 }
 
-syncer::ModelSafeGroup ProxyDataTypeController::model_safe_group() const {
-  DCHECK(syncer::ProxyTypes().Has(type_));
-  return syncer::GROUP_PASSIVE;
-}
-
-ChangeProcessor* ProxyDataTypeController::GetChangeProcessor() const {
-  return NULL;
-}
-
 std::string ProxyDataTypeController::name() const {
   // For logging only.
   return syncer::ModelTypeToString(type());
@@ -70,4 +63,10 @@ void ProxyDataTypeController::OnModelLoaded() {
   NOTIMPLEMENTED();
 }
 
+void ProxyDataTypeController::ActivateDataType(
+    BackendDataTypeConfigurer* configurer) {}
+
+void ProxyDataTypeController::DeactivateDataType(
+    BackendDataTypeConfigurer* configurer) {}
+
 }  // namespace sync_driver