jmx-dev RFR 8047073: Some javax/management/ fails with JFR

[Jaroslav Bachorik]

Please, review this test change.

Issue : https://bugs.openjdk.java.net/browse/JDK-8047073
Webrev: http://cr.openjdk.java.net/~jbachorik/8047073/webrev.00

When the test is run with JFR the MBean platform server is initialized 
before the main method is executed. Therefore, setting the system 
properties in the code to influence JMX behaviour is ineffective. The 
system properties need to be set in the @run clause of the JTreg test.

Thanks,

-JB-