RFR(XS) : 8186095 : upgrade to jtreg 4.2 b08

[Igor Ignatyev]

http://cr.openjdk.java.net/~iignatyev//8186095/webrev.00/index.html
> 14 lines changed: 1 ins; 0 del; 13 mod; 

Hi all,

could you please review this small patch which bumps up jtreg version?
besides updating jib profiles and all TEST.ROOT files, the fix updates 
hotspot/test/runtime/Metaspace/FragmentMetaspaceSimple.java test not to rely on 
having "library" test.Empty class in 'test.classes' and put test.Empty class in 
the workdir instead.

testing: :hotspot_all, {jdk,langtools,nashorn,jaxp}/test/:tier[1-3]

Thanks,
-- Igor