MDEV-20091 DROP TEMPORARY table is logged despite no CREATE was logged

MDEV-5589 commit set up a policy to skip DROP TEMPORARY TABLE binary logging
in case the target table has not been "CREATEed" in binlog (no CREATE
Query-log-event was logged into the binary log).

It turns out that

1. the rule did not cover non-existing table DROPped with IF-EXISTS clause.
   The logged-create knowledge for the non-existing one does not even need
   MDEV-5589 patch, and

2. connection close disobeys it to trigger automatic DROP-IF-EXISTS
   binlogging.

Either 1 or 2 or even both is/are also responsible for unexpected binlog
records observed in MDEV-17863, actually rendering a referred
@@global.read_only irrelevant as far as the described stored procedure
definition *and* the ROW binlog-format are concerned.

mysql-test/suite/binlog/r/binlog_parallel_replication_marks_row.result

@@ -89,6 +89,4 @@ BEGIN
 # server id 1  end_log_pos # 	Table_map: `test`.`t1` mapped to number #
 # server id 1  end_log_pos # 	Write_rows: table id # flags: STMT_END_F
 COMMIT/*!*/;
-# server id 1  end_log_pos # 	GTID #-#-# ddl
-DROP /*!40005 TEMPORARY */ TABLE IF EXISTS `t5`
 DROP TABLE t1;