RFR: 8145704: Make test for classinit logging more robust.

[Max Ockner]

Hello,

Please review this small fix for the classinit logging test. This test 
was submitted before it was standard to test that logging disappears 
when the level is "off". The test now contains this case.

bug: https://bugs.openjdk.java.net/browse/JDK-8145704
webrev: http://cr.openjdk.java.net/~mockner/8145704/

Test passes.

Thanks,
Max