LP #1647741: Backport "InnoDB shutdown hangs if innodb_force_recovery >= 3 skipped any rollback" from 5.7

**Reported in Launchpad by Laurynas Biveinis last update 09-12-2016 10:48:59

On 5.6 trunk, innodb.innodb_bug-13628249 fails intermittently with

innodb.innodb_bug-13628249 w4 [ fail ]
Test ended at 2016-12-02 15:20:31

CURRENT_TEST: innodb.innodb_bug-13628249
mysqltest: In included file "./include/wait_until_connected_again.inc":
included from ./include/wait_until_connected_again.inc at line 25:
At line 25: Server failed to restart

The result from queries just before the failure was:
call mtr.add_suppression('InnoDB: Failed to find tablespace for table \'"mysql"."slave_master_info"\' in the cache');
call mtr.add_suppression('InnoDB: Failed to find tablespace for table \'"mysql"."slave_relay_log_info"\' in the cache');
call mtr.add_suppression('InnoDB: Failed to find tablespace for table \'"mysql"."slave_worker_info"\' in the cache');
call mtr.add_suppression('InnoDB: Failed to find tablespace for table \'"test"."t1"\' in the cache');
call mtr.add_suppression('InnoDB: Allocated tablespace [0-9], old maximum was [0-9]');

1. Stop server

2. Restart server.

3. Restart server.
   CREATE TABLE t1(c1 INT PRIMARY KEY) ENGINE=InnoDB STATS_PERSISTENT=0;
   BEGIN;
   INSERT INTO t1 VALUES(1), (2), (3), (4);
   SET SESSION debug="+d,crash_commit_before";
   COMMIT;
   ERROR HY000: Lost connection to MySQL server during query
   SELECT COUNT IN (0,4) yes FROM t1;
   yes
   1
   safe_process[30106]: Child process: 30107, exit: 1
   ...
   2016-12-02 18:12:07 30206 [Note] InnoDB: Starting shutdown...
   2016-12-02 18:13:07 30206 [Note] InnoDB: Waiting for 1 active transactions to finish
   2016-12-02 18:14:07 30206 [Note] InnoDB: Waiting for 1 active transactions to finish
   2016-12-02 18:15:12 30206 [Note] InnoDB: Waiting for 1 active transactions to finish
   2016-12-02 18:16:13 30206 [Note] InnoDB: Waiting for 1 active transactions to finish
   2016-12-02 18:17:13 30206 [Note] InnoDB: Waiting for 1 active transactions to finish
   2016-12-02 18:18:13 30206 [Note] InnoDB: Waiting for 1 active transactions to finish
   2016-12-02 18:19:13 30206 [Note] InnoDB: Waiting for 1 active transactions to finish
   2016-12-02 18:20:13 30206 [Note] InnoDB: Waiting for 1 active transactions to finish

The fix appears to backport

commit b7a0c7f5527647e8e3bdae9c7bbef922f8a1b5e4
Author: Marko M<C3><A4>kel<C3><A4> <marko.makela@oracle.com>
Date: Tue Apr 14 09:25:23 2015 +0300

Bug#20874411 INNODB SHUTDOWN HANGS IF INNODB_FORCE_RECOVERY>=3
SKIPPED ANY ROLLBACK

trx_sys_any_active_transactions(): If any prepared ACTIVE transactions
exist, and their rollback was prevented by innodb_force_recovery,
convert these transactions to XA PREPARE state in the main-memory
data structures, so that shutdown will proceed normally. These transactions
will again recover as ACTIVE on the next restart, and they will be rolled
back unless innodb_force_recovery>=3 again.

trx_undo_fake_prepared(): An auxiliary function to set an undo log to
PREPARED state.

RB: 8610
Reviewed-by: Jimmy Yang <jimmy.yang@oracle.com>