RFR 8197518: Kerberos krb5 authentication: AuthList's put method leads to performance issue

[Weijun Wang]

Please take a review at

   http://cr.openjdk.java.net/~weijun/8197518/webrev.00/

Two notes:

1. I tried list.subList(here, end).clear() but it's not faster.

2. I have looked at ConcurrentHashMap + ConcurrentSkipListMap but will need more time to verify its correctness and measure the performance gain. Since the bug is reported on 8u, a safer fix looks better.

Noreg-perf.

Thanks
Max