Merge pull request #3355 from matrix-org/rav/fix_federation_backfill

Fix federation backfill from sqlite servers

synapse/storage/state.py

@@ -272,7 +272,7 @@ def _get_state_groups_from_groups_txn(self, txn, groups, types=None):
                 for typ in types:
                     if typ[1] is None:
                         where_clauses.append("(type = ?)")
-                        where_args.extend(typ[0])
+                        where_args.append(typ[0])
                         wildcard_types = True
                     else:
                         where_clauses.append("(type = ? AND state_key = ?)")