RFR 8098580: drainRefQueueBounds() puts pressure on pool.size()

[Anthony Scarpino]

Hi,

I need a review of this change to SunPKCS11 where it's a bit smarter in 
disposing of native library object by reusing the same pkcs11 session is 
possible.  Additionally changes to the session pool to fix a performance 
bottleneck.

http://cr.openjdk.java.net/~ascarpino/8098580/webrev/

thanks

Tony