Request for review (s) - 8014546 :UseAdaptiveGCBoundary is broken

[Jon Masamitsu]

A recent changeset effectively removed the initialization of
performance counters used  by the option UseAdaptiveGCBoundary

This changeset is built on top of the one for 8014546 and the
webrev comes in two parts.

The fix plus the test

http://cr.openjdk.java.net/~jmasa/8015851/webrev.00/

Some cleanups of the code

http://cr.openjdk.java.net/~jmasa/8015851/webrev_refactor.00/

Thanks.

Jon