innodb_fts.sync fails in buildbot with wrong result

innodb_fts.sync 'innodb'                 w1 [ fail ]

        Test ended at 2017-12-11 18:22:37

CURRENT_TEST: innodb_fts.sync

--- /mnt/buildbot/build/mariadb-10.2.12/mysql-test/suite/innodb_fts/r/sync.result	2017-12-11 10:16:57.000000000 +0200

+++ /mnt/buildbot/build/mariadb-10.2.12/mysql-test/suite/innodb_fts/r/sync.reject	2017-12-11 18:22:36.000000000 +0200

@@ -109,7 +109,7 @@

 SELECT * FROM t1 WHERE MATCH(title) AGAINST ('mysql database');

 FTS_DOC_ID	title

 1	database

-2	mysql

+3	mysql

 DROP TABLE t1;

 # Case 4: Test sync commit & rollback in background

 CREATE TABLE t1(

mysqltest: Result content mismatch