The grid shows what GetOfficeByCountryState('USA', 'CA') returns: pass "CALL GetOfficeByCountryState(?, ?)" as the SQL and the parameter values as the second argument.
This demo calls the GetOfficeByCountryState procedure, which isn't in the database yet. Stored procedures aren't part of the sample database, so they are installed separately:
examples/SampleDB/mysql_storedproc.sql into the sample database that conf.php uses:
mysql -u USER -p sampledb < examples/SampleDB/mysql_storedproc.sqlor open the file in phpMyAdmin, MySQL Workbench or another client and run it.
CREATE ROUTINE privilege to import it and EXECUTE to call the procedures.