Reapply a MySQL 5.6.23/5.7.10 Oracle Bug#20029625 fix that was inadvertently reverted in MariaDB 10.2.2

The fix https://github.com/mysql/mysql-server/commit/716f97e2714e70f35d2dc01f0125ed833c62b408
was inadvertently reverted in
commit 2e814d47
"Merge InnoDB 5.7 from mysql-5.7.9".

Reapply the fix, because the test of the bug would fail
after merging MDEV-13838, which replaced an earlier incorrect
bug fix with a correct one.