MDEV-9969 mysql_install_db error processing ignore_db_dirs.

        test failed on Windows so fixed by testing slightly differently.

mysql-test/r/mysqld_option_err.result

@@ -5,5 +5,4 @@ Test non-numeric value passed to number option.
 Test that bad value for plugin enum option is rejected correctly.
 Test that --help --verbose works
 Test that --not-known-option --help --verbose gives error
-Test that specifying same directory several times handled properly.
 Done.

mysql-test/t/bootstrap.test

@@ -89,3 +89,13 @@ drop table t1;
 --replace_result .dll .so
 select * from mysql.plugin;
 truncate table mysql.plugin;
+
+
+#
+# MDEV-9969 mysql_install_db error processing ignore_db_dirs.
+#
+--write_file $MYSQLTEST_VARDIR/tmp/bootstrap_9969.sql
+use test;
+EOF
+--exec $MYSQLD_BOOTSTRAP_CMD --ignore-db-dirs='some_dir' --ignore-db-dirs='some_dir' < $MYSQLTEST_VARDIR/tmp/bootstrap_9969.sql >> $MYSQLTEST_VARDIR/tmp/bootstrap.log 2>&1
+--remove_file $MYSQLTEST_VARDIR/tmp/bootstrap_9969.sql

mysql-test/t/mysqld_option_err.test

@@ -56,12 +56,4 @@ mkdir $MYSQLTEST_VARDIR/tmp/mysqld_option_err;
 --error 2
 --exec $MYSQLD_BOOTSTRAP_CMD --not-known-option --help --verbose >>$MYSQLTEST_VARDIR/tmp/mysqld_option_err/mysqltest.log 2>&1
 
-#
-# MDEV-9969 mysql_install_db error processing ignore_db_dirs.
-#
-
---echo Test that specifying same directory several times handled properly.
-
---exec echo "" | $MYSQLD_BOOTSTRAP_CMD --skip-networking --datadir=$MYSQLTEST_VARDIR/tmp/mysqld_option_err --skip-grant-tables --ignore-db-dirs='some_dir' --ignore-db-dirs='some_dir'  >>$MYSQLTEST_VARDIR/tmp/mysqld_option_err/mysqltest.log 2>&1
-
 --echo Done.