Pruning fix for SYSTEM_TIME INTERVAL partitioning.
Allocating one more element in range_int_array for CURRENT partition
is required for RANGE pruning to work correctly
(get_partition_id_range_for_endpoint()).
Current easy fix is not possible, because SELECT clones ha_partition
and then closes the clone which leads to unclosed transaction in
partitions we forcely prune out. We cound solve this by closing these
partitions (and release from transaction) in
change_partitions_to_open() at versioning conditions stage, but this
is problematic because table lock is acquired for each partition at
open stage and therefore must be released when we close partition
handler in change_partitions_to_open(). More details in MDEV-20376.
This should change after MDEV-20250 where mechanism of opening
partitions will be improved.
This reverts commit cdbac54df0.
Don't use hidden system time in versioning,
but keep the system time logic in THD
to workaround low-res system clock and
replication not versioned to versioned.
This reverts MDEV-14788 (System versioning cannot
be based on local timestamps, as it is now).
Versioning is based on local timestamps again,
but timestamps are protected by MDEV-15923
(option to control who can set session @@timestamp).
