Comment 5 for bug 1667307

What is happening here?

1) When binlog_rows_query_log_events is enabled Rows_query_log_event is created, written to binary log on master.

2) Slave is reading read this event from relay log and applying it, see Rows_query_log_event::do_apply_event(). When the event is applied the event itself is stored in Relay_log_info::rows_query_ev:

int Rows_query_log_event::do_apply_event(Relay_log_info const *rli)
{
  DBUG_ENTER("Rows_query_log_event::do_apply_event");
  DBUG_ASSERT(rli->info_thd == thd);
  /* Set query for writing Rows_query log event into binlog later.*/
  thd->set_query(m_rows_query, strlen(m_rows_query));

  DBUG_ASSERT(rli->rows_query_ev == NULL);

  const_cast<Relay_log_info*>(rli)->rows_query_ev= this;
  /* Tell worker not to free the event */
  worker= NULL;
  DBUG_RETURN(0);
}

3) Usually Relay_log_info::rows_query_ev is removed with the following stack trace:

#0 Rows_query_log_event::~Rows_query_log_event (this=0x7fff9401df00, __in_chrg=<optimized out>, __vtt_parm=<optimized out>)
    at ./sql/log_event.h:3795
#1 0x0000000001958d1e in Relay_log_info::cleanup_context (this=0x7fffa40413d0, thd=0x7fff94000950, error=false)
    at ./sql/rpl_rli.cc:1777
#2 0x00000000018d984b in rows_event_stmt_cleanup (rli=0x7fffa40413d0, thd=0x7fff94000950) at ./sql/log_event.cc:11297
#3 0x00000000018d9500 in Rows_log_event::do_apply_event (this=0x7fff94012fc0, rli=0x7fffa40413d0)
    at ./sql/log_event.cc:11175
#4 0x00000000018c00c7 in Log_event::apply_event (this=0x7fff94012fc0, rli=0x7fffa40413d0) at ./sql/log_event.cc:3371
#5 0x0000000001938e0f in apply_event_and_update_pos (ptr_ev=0x7ffff139e8a0, thd=0x7fff94000950, rli=0x7fffa40413d0)
    at ./sql/rpl_slave.cc:4750
#6 0x000000000193a5d7 in exec_relay_log_event (thd=0x7fff94000950, rli=0x7fffa40413d0) at ./sql/rpl_slave.cc:5265
#7 0x00000000019418eb in handle_slave_sql (arg=0x7fffa4139800) at ./sql/rpl_slave.cc:7461
#8 0x0000000001e6a679 in pfs_spawn_thread (arg=0x7fffa413d640) at ./storage/perfschema/pfs.cc:2188
#9 0x00007ffff71616ba in start_thread (arg=0x7ffff139f700) at pthread_create.c:333
#10 0x00007ffff65f682d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

But if we look into Rows_log_event::do_apply_event() the function rows_event_stmt_cleanup() is called at the end:

end:
  if (get_flags(STMT_END_F))
  {
    if((error= rows_event_stmt_cleanup(rli, thd)))
    {