BUG#26625: crash in range optimizer (out of mem)  - Define Sql_alloc::operator new() as thow() so that C++ compiler   handles NULL return values (there is no testcase as there is no portable way to set limit on the  amount of memory that a process can allocate)
BUG#26625: crash in range optimizer (out of mem) 
- Define Sql_alloc::operator new() as thow() so that C++ compiler
  handles NULL return values
(there is no testcase as there is no portable way to set limit on the 
amount of memory that a process can allocate)

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