commit_try_rebuild(): Only invoke trx_t::drop_table_statistics()
if both InnoDB statistics tables are accessible (and exclusively
locked by the current transaction). This avoids a crash due to
ut_a(sym_node->table != NULL) in pars_retrieve_table_def().

The crash was repeated on a partial copy of a MariaDB 10.3 data
directory that lacked the *.ibd files for the statistics tables.

fil_space_t::flush<false>(): If the CLOSING flag is set,
the file may already have been closed, resulting in EBADF
being returned by fdatasync(). In any case, the
thread that had set the flag should take care of invoking
os_file_flush_func().

The crash occurred during the execution of FLUSH TABLES...FOR EXPORT.

Tested by: Matthias Leich

Also refer to the service file for startup.

Also include the ftp.mariadb.org script rather than old name.

This fixes up 25b91c3f

galera_sr.GCF-1060 'innodb'              w2 [ fail ]  timeout after 900 seconds

galera_3nodes.galera_ssl_reload At line 50: mysql_shutdown failed
galera_3nodes.galera_ssl_reload : MDEV-30172 At line 50: mysql_shutdown failed
galera_3nodes.GCF-354 : mysqltest: At line 39: query 'DROP TABLE test.t1' failed: 1047: WSREP has not yet prepared node for application use
galera_3nodes.GCF-354 : mysqltest: At line 30: query 'INSERT INTO test.t1 values (1)' failed: 1180: Got error 6 "No such device or address"

galera_wan : [ERROR] WSREP: /home/buildbot/buildbot/build/gcs/src/gcs_state_msg.cpp:gcs_state_msg_get_quorum():947: Failed to establish quorum.

Merge Jan's bb-10.6-merge-jan branch:

MDEV-30172 Galera test case cleanup

    * Delete tests that are not supported and not going to be supported
      any time soon
    * Fix result set on tests that are not run on bb
    * Fix tests that fail because of auto increment offset
    * Make sure that disabled tests have open bug report

galera.galera_bf_abort_at_after_statement disabled by Daniel Black

Adjust galera/galera_3nodes disabled tests.