RFR 8210300: runtime/MemberName/MemberNameLeak.java fails with RuntimeException

[Patricio Chilano]

Hi all,

Could you review this small fix to tests CleanProtectionDomain.java and 
MemberNameLeak.java?
It adds flag UnlockDiagnosticVMOptions needed in product builds. It also 
calls System.gc() periodically to avoid relaying on a single call, and 
adds a short sleep between polls.

Bug URL: https://bugs.openjdk.java.net/browse/JDK-8210300
Webrev URL: http://cr.openjdk.java.net/~pchilanomate/8210300.01/webrev

Thanks,
Patricio