sync: migrate invalidation state from syncable::Directory to InvalidationStorage

sync/notifier/sync_notifier_factory.h

Index: sync/notifier/sync_notifier_factory.h
diff --git a/sync/notifier/sync_notifier_factory.h b/sync/notifier/sync_notifier_factory.h
index ab3268f1248d9f541fbeda94058166bff130f481..9e14fcd154ad75c28cb51558ea024f2f294da84b 100644
--- a/sync/notifier/sync_notifier_factory.h
+++ b/sync/notifier/sync_notifier_factory.h
@@ -39,6 +39,7 @@ class SyncNotifierFactory {
   const notifier::NotifierOptions notifier_options_;
   const std::string client_info_;
   const InvalidationVersionMap initial_max_invalidation_versions_;
+  const std::string initial_invalidation_state_;
   const browser_sync::WeakHandle<InvalidationStateTracker>
       invalidation_state_tracker_;
 };