MDEV-12290 Wrong timestamps in binary log causes replication issues
MDEV-12290 Wrong timestamps in binary log causes replication issues

Binlog_background_thread does not make a call to set_time(), And when
we call binlog_checkpoint_log_event->write() , we write the wrong timestamp.
In this patch we correct this by calling thd->set_time().

natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2