[Sync] Plumb initial type set from engine to DTM.

components/browser_sync/profile_sync_service_mock.h

Index: components/browser_sync/profile_sync_service_mock.h
diff --git a/components/browser_sync/profile_sync_service_mock.h b/components/browser_sync/profile_sync_service_mock.h
index 5e8c5ca64f8f806fa9e72d08f0748830058b5ffa..02ea58627e31d259f67fdd4a143804721867b16f 100644
--- a/components/browser_sync/profile_sync_service_mock.h
+++ b/components/browser_sync/profile_sync_service_mock.h
@@ -33,9 +33,10 @@ class ProfileSyncServiceMock : public ProfileSyncService {
 
   virtual ~ProfileSyncServiceMock();
 
-  MOCK_METHOD4(
+  MOCK_METHOD5(
       OnEngineInitialized,
-      void(const syncer::WeakHandle<syncer::JsBackend>&,
+      void(syncer::ModelTypeSet initial_types,
+           const syncer::WeakHandle<syncer::JsBackend>&,
            const syncer::WeakHandle<syncer::DataTypeDebugInfoListener>&,
            const std::string&,
            bool));