MDEV-15472: Assertion `!is_set() || (m_status == DA_OK_BULK && is_bulk_op())' failure

MariaDB differs from the upstream for "DDL-like" command. For these,
it sets binlog_format=STATEMENT for the duration of the statement.
This doesn't play well with MyRocks, which tries to prevent DML
commands with binlog_format!=ROW.

Also, if Locked_tables_list::reopen_tables() returned an error, then
close_cached_tables should propagate the error condition and not silently
consume it (it's difficult to have test coverage for this because this
error condition is rare)

sql/sql_base.cc

@@ -481,7 +481,7 @@ bool close_cached_tables(THD *thd, TABLE_LIST *tables,
       old locks. This should always succeed (unless some external process
       has removed the tables)
     */
-    thd->locked_tables_list.reopen_tables(thd);
+    result= thd->locked_tables_list.reopen_tables(thd);
     /*
       Since downgrade_lock() won't do anything with shared
       metadata lock it is much simpler to go through all open tables rather

storage/rocksdb/ha_rocksdb.cc

@@ -10056,6 +10056,7 @@ int ha_rocksdb::external_lock(THD *const thd, int lock_type) {
       thd->lex->sql_command != SQLCOM_LOCK_TABLES &&  // (*)
       thd->lex->sql_command != SQLCOM_ANALYZE &&   // (**)
       thd->lex->sql_command != SQLCOM_OPTIMIZE &&  // (**)
+      thd->lex->sql_command != SQLCOM_FLUSH &&  // (**)
       my_core::thd_binlog_filter_ok(thd)) {
     my_error(ER_REQUIRE_ROW_BINLOG_FORMAT, MYF(0));
     DBUG_RETURN(HA_ERR_UNSUPPORTED);

storage/rocksdb/mysql-test/rocksdb/r/mariadb_port_rpl.result

+#
+# MDEV-15472: Assertion `!is_set() || (m_status == DA_OK_BULK && is_bulk_op())' failure ...
+#
+select @@log_bin;
+@@log_bin
+1
+select @@binlog_format;
+@@binlog_format
+ROW
+CREATE OR REPLACE TABLE t1 (i INT) ENGINE=RocksDB;
+LOCK TABLE t1 WRITE;
+FLUSH TABLES;
+UNLOCK TABLES;
+DROP TABLE t1;

storage/rocksdb/mysql-test/rocksdb/t/mariadb_port_rpl.test

+--source include/have_rocksdb.inc
+--source include/have_binlog_format_row.inc
+
+--echo #
+--echo # MDEV-15472: Assertion `!is_set() || (m_status == DA_OK_BULK && is_bulk_op())' failure ...
+--echo #
+select @@log_bin;
+select @@binlog_format;
+CREATE OR REPLACE TABLE t1 (i INT) ENGINE=RocksDB;
+LOCK TABLE t1 WRITE;
+FLUSH TABLES;
+UNLOCK TABLES;
+DROP TABLE t1;
+