Fix for BUG#12082 (assert failure when the query fails to get a lock for record in 'const' table):  Set table->key_read back to 0 regardless of whether join_read_const() succeeded or not.
Fix for BUG#12082 (assert failure when the query fails to get a lock for record in 'const' table):
 Set table->key_read back to 0 regardless of whether join_read_const() succeeded or not.




natsys/mariadb_10.2,flynn1973/mariadb-aix,davidl-zend/zenddbi,ollie314/server,davidl-zend/zenddbi,flynn1973/mariadb-aix,davidl-zend/zenddbi,flynn1973/mariadb-aix,davidl-zend/zenddbi,flynn1973/mariadb-aix,ollie314/server,natsys/mariadb_10.2,davidl-zend/zenddbi,davidl-zend/zenddbi,slanterns/server,flynn1973/mariadb-aix,flynn1973/mariadb-aix,ollie314/server,natsys/mariadb_10.2,natsys/mariadb_10.2,flynn1973/mariadb-aix,ollie314/server,ollie314/server,flynn1973/mariadb-aix,natsys/mariadb_10.2,davidl-zend/zenddbi,ollie314/server,natsys/mariadb_10.2,ollie314/server,ollie314/server,ollie314/server,flynn1973/mariadb-aix,davidl-zend/zenddbi,davidl-zend/zenddbi,ollie314/server,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,flynn1973/mariadb-aix,flynn1973/mariadb-aix,davidl-zend/zenddbi,davidl-zend/zenddbi,natsys/mariadb_10.2,ollie314/server,natsys/mariadb_10.2