The sync_slave_with_master command in mysqltest is patched in
MySQL Cluster to make sure that the current epoch is binlogged
entirely before getting master binlog position.
Bug #18375920 NDB TESTING : SYNC_SLAVE_WITH_MASTER CAN TIMEOUT AND CONTINUE

sync_slave_with_master are more and more being replaced by
include/sync_slave_sql_with_master.inc, for example in coming
WL#7205 Make the MTR rpl suite GTID_MODE agnostic

This patch imitates the functionality added to sync_slave_with_master
in sync_slave_sql_with_master.inc by adding a file
wait_for_ndb_committed_to_binlog.inc with logic that first look at
latest_trans_epoch in SHOW ENGINE NDB STATUS and then waits until
latest_handled_binlog_epoch catch up.

Changes are only done to mysql-test subsystem.