[Sync] Enable adding notifier observers from ProfileSyncService

sync/internal_api/sync_manager_impl.cc

Index: sync/internal_api/sync_manager_impl.cc
diff --git a/sync/internal_api/sync_manager_impl.cc b/sync/internal_api/sync_manager_impl.cc
index b400c511dbed422f9a673e02d32397309c361fe7..950e280370a16d871598251792294b8bcf257481 100644
--- a/sync/internal_api/sync_manager_impl.cc
+++ b/sync/internal_api/sync_manager_impl.cc
@@ -733,8 +733,15 @@ void SyncManagerImpl::UpdateCredentials(
 void SyncManagerImpl::UpdateEnabledTypes(
     const ModelTypeSet& enabled_types) {
   DCHECK(thread_checker_.CalledOnValidThread());
-  sync_notifier_->UpdateRegisteredIds(this,
-                                      ModelTypeSetToObjectIdSet(enabled_types));
+  sync_notifier_->UpdateRegisteredIds(
+      this,
+      ModelTypeSetToObjectIdSet(enabled_types));
+}
+
+void SyncManagerImpl::UpdateRegisteredInvalidationIds(
+    SyncNotifierObserver* handler, const ObjectIdSet& ids) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  sync_notifier_->UpdateRegisteredIds(handler, ids);
 }
 
 void SyncManagerImpl::SetEncryptionPassphrase(