RFR 9: 8160848 : Add diagnostics to java/lang/ProcessBuilder/Zombies

[Roger Riggs]

Please review adding diagnostics to an intermittently failing test; 
java/lang/ProcessBuilder/Zombies.java.

Recently, the Zombies test has started intermittently reporting 1 
Zombies errors on Solaris.

Webrev:
  http://cr.openjdk.java.net/~rriggs/webrev-zombies-8160848/

The original issue is open pending more information:
  https://bugs.openjdk.java.net/browse/JDK-8160151

Thanks, Roger