Bug#20816223 InnoDB crash on shutdown

if XA PREPARE transactions hold explicit locks.

innobase_shutdown_for_mysql(): Call trx_sys_close() before lock_sys_close()
(and dict_close()) so that trx_free_prepared() will see all locks intact.

RB: 8561
Reviewed-by: Vasil Dimov <vasil.dimov@oracle.com>

mysql-test/suite/innodb/r/xa_recovery.result

+CREATE TABLE t1 (a INT) ENGINE=InnoDB;
+INSERT INTO t1 VALUES (1);
+XA START 'x';
+UPDATE t1 set a=2;
+XA END 'x';
+XA PREPARE 'x';
+call mtr.add_suppression("Found 1 prepared XA transactions");
+SELECT * FROM t1 LOCK IN SHARE MODE;
+SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;
+SELECT * FROM t1;
+a
+2
+XA ROLLBACK 'x';
+SELECT * FROM t1;
+a
+1
+DROP TABLE t1;

mysql-test/suite/innodb/t/xa_recovery.test

+--source include/have_innodb.inc
+
+CREATE TABLE t1 (a INT) ENGINE=InnoDB;
+INSERT INTO t1 VALUES (1);
+connect (con1,localhost,root);
+XA START 'x'; UPDATE t1 set a=2; XA END 'x'; XA PREPARE 'x';
+connection default;
+
+call mtr.add_suppression("Found 1 prepared XA transactions");
+
+# Kill and restart the server.
+-- exec echo "wait" > $MYSQLTEST_VARDIR/tmp/mysqld.1.expect
+-- shutdown_server 0
+-- source include/wait_until_disconnected.inc
+
+-- exec echo "restart" > $MYSQLTEST_VARDIR/tmp/mysqld.1.expect
+-- enable_reconnect
+-- source include/wait_until_connected_again.inc
+-- disable_reconnect
+
+disconnect con1;
+connect (con1,localhost,root);
+--send SELECT * FROM t1 LOCK IN SHARE MODE
+
+connection default;
+let $wait_condition=
+  select count(*) = 1 from information_schema.processlist
+  where state = 'Sending data' and
+        info = 'SELECT * FROM t1 LOCK IN SHARE MODE';
+--source include/wait_condition.inc
+
+--source include/restart_mysqld.inc
+
+disconnect con1;
+
+SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;
+SELECT * FROM t1;
+XA ROLLBACK 'x';
+SELECT * FROM t1;
+
+DROP TABLE t1;

storage/innobase/srv/srv0start.c

 /*****************************************************************************
 
-Copyright (c) 1996, 2013, Oracle and/or its affiliates. All rights reserved.
+Copyright (c) 1996, 2015, Oracle and/or its affiliates. All rights reserved.
 Copyright (c) 2008, Google Inc.
 Copyright (c) 2009, Percona Inc.
 
@@ -2230,9 +2230,9 @@ innobase_shutdown_for_mysql(void)
 
 	ibuf_close();
 	log_shutdown();
-	lock_sys_close();
 	trx_sys_file_format_close();
 	trx_sys_close();
+	lock_sys_close();
 
 	mutex_free(&srv_monitor_file_mutex);
 	mutex_free(&srv_dict_tmpfile_mutex);