RFR (S): 8140585: PLAB statistics are flushed too late

[Thomas Schatzl]

Hi all,

  can I have reviews for this bug M. Chernov reported a few days ago?
PLAB statistics flushing (i.e. updating the G1EvacStats data structure)
is done too late so that the PrintPLAB printout shows and uses the
previous' GCs values, which may negatively affect PLAB statistics
measurements.

CR:
https://bugs.openjdk.java.net/browse/JDK-8140585
Webrev:
http://cr.openjdk.java.net/~tschatzl/8140585/webrev
Testing:
jtreg, vm.gc, new jtreg test

Thanks,
  Thomas