main.delete_use_source fails in buildbot and outside with wrong plan

main.delete_use_source 'innodb'          w1 [ fail ]

        Test ended at 2017-07-08 01:42:52

CURRENT_TEST: main.delete_use_source

--- /usr/local/mariadb-10.2.7-linux-x86_64/mysql-test/r/delete_use_source.result	2017-07-07 23:42:11.000000000 +0300

+++ /usr/local/mariadb-10.2.7-linux-x86_64/mysql-test/r/delete_use_source.reject	2017-07-08 01:42:52.427051960 +0300

@@ -44,8 +44,8 @@

 start transaction;

 explain delete from v1 where (select count(*) from t1 b where b.c1=v1.c1) = 500 limit 1;

 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra

-1	PRIMARY	t1	range	c1	c1	4	NULL	550	Using where

-2	DEPENDENT SUBQUERY	b	ref	c1	c1	4	test.t1.c1	82	Using index

+1	PRIMARY	t1	ALL	c1	NULL	NULL	NULL	472	Using where

+2	DEPENDENT SUBQUERY	b	ref	c1	c1	4	test.t1.c1	113	Using index

 delete from v1 where (select count(*) from t1 b where b.c1=v1.c1) = 500 limit 1;

 affected rows: 1

 delete from v1 where (select count(*) from t1 b where b.c1=v1.c1) = 500 limit 1;

@@ -60,8 +60,8 @@

 start transaction;

 explain delete from v1 where (select count(*) from t1 b where b.c1=v1.c1) = 500;

 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra

-1	PRIMARY	t1	ALL	c1	NULL	NULL	NULL	717	Using where

-2	DEPENDENT SUBQUERY	b	ref	c1	c1	4	test.t1.c1	82	Using index

+1	PRIMARY	t1	ALL	c1	NULL	NULL	NULL	472	Using where

+2	DEPENDENT SUBQUERY	b	ref	c1	c1	4	test.t1.c1	113	Using index

 delete from v1 where (select count(*) from t1 b where b.c1=v1.c1) = 500 ;

 affected rows: 500

 select count(*) from v1 where c1=0;

mysqltest: Result length mismatch