Review request for JDK-8073706

[Attila Szegedi]

Please review JDK-8073706 at 
<http://cr.openjdk.java.net/~attila/8073706/webrev.00> for 
<https://bugs.openjdk.java.net/browse/JDK-8073706>

While running test262parallel, it seldom run into this livelock. It's hard to 
reproduce, and I fail to see how it can happen, so I instead changed the 
heuristic to make sure the livelock can't happen.

Thanks,
  Attila.