RFR(S): 8068613: Wrong number of objects pending finalization start

[Mattias Tobiasson]

Hi,
Could I please have a review of this test bug fix.

bug: https://bugs.openjdk.java.net/browse/JDK-8068613
webrev: http://cr.openjdk.java.net/~ykantser/8068613/webrev.01

On line 90 and on line 246 (in the old version) the test does a short 
wait between
Runtime.getRuntime().runFinalization() and
MemoryMXBean.getObjectPendingFinalizationCount()

The test expects getObjectPendingFinalizationCount() to return 0,
but that sometimes fails on really slow servers.

The fix will loop until getObjectPendingFinalizationCount() returns 0,
or until it gives up after 100 tries.

Thanks,
Mattias