Analysis: wsrep_applier_thread shutdown signaling does not always work
correctly causing a timing problem where main thread is waiting in a
condition variable a signal that all worker threads to end.
Merged lp:maria/maria-10.0-galera up to revision 3879.
Added a new functions to handler API to forcefully abort_transaction,
producing fake_trx_id, get_checkpoint and set_checkpoint for XA. These
were added for future possiblity to add more storage engines that
could use galera replication.
Decoupled wsrep thread count from connection count. By doing so,
the number of wsrep threads (applier/rollbacker) would no longer
affect the threads_connected status variable and thus maximum
allowable user connections limit would be @@max_connections.
Also introduced a new status variable 'wsrep_thread_count' to hold
the number of wsrep applier/rollbacker threads.
Added a test case.
mysql_tzinfo_to_sql tries to set wsrep_replicate_myisam
as SESSION variable, while its a GLOBAL-only system variable,
and thus the resulting sql would fail to load.
Fixed by changing the scope to GLOBAL in the SET command.
Also added following include files to facilitate testing :
* include/have_wsrep.inc
* include/not_wsrep.inc
* include/have_wsrep_enabled.inc
