Null-merge the revert of MDEV-24589

While MDEV-24589 causes the regression
MDEV-25491 Race condition between DROP TABLE and purge of
SYS_INDEXES record
we must not revert it from 10.6, because MDEV-24589 is a prerequisite for
MDEV-25180 Atomic ALTER TABLE
that is targeting 10.6. The regression will be dealt with later.