8043277: Update jdk regression tests to extend the default security policy instead of override
Reviewed-by: alanb, mullan, chegar, sla
grant {
permission java.io.FilePermission "<<ALL FILES>>","read";
permission java.util.PropertyPermission "test.jdk","read";
permission java.util.PropertyPermission "test.src","read";
permission java.util.PropertyPermission "user.dir","read";
};