addresses #1057

add DB_PRELOCKED flag where applicable in add_index

git-svn-id: file:///svn/mysql/tokudb-engine/src@5410 c7de825b-a66e-492c-adef-691d508d4ae1

storage/tokudb/ha_tokudb.cc

@@ -4183,7 +4183,7 @@ int ha_tokudb::add_index(TABLE *table_arg, KEY *key_info, uint num_of_keys) {
                 goto cleanup;
             }
         }
-        cursor_ret_val = tmp_cursor->c_get(tmp_cursor, &current_primary_key, &row, DB_NEXT);
+        cursor_ret_val = tmp_cursor->c_get(tmp_cursor, &current_primary_key, &row, DB_NEXT | DB_PRELOCKED);
     }
     error = txn->commit(txn, 0);
     assert(error == 0);