RFR[s]: 8201633 Problems with AES-GCM native acceleration

[Anthony Scarpino]

I need a review of this change which is to help the AES/GCM intrinsic 
activate on large data sizes.  It's not the ideal resolution, which 
splits up the crypto operation in chucks, but I significantly improves 
performance for larger data sizes.  Additionally there is an 
optimization to not allocated and use an unnecessary buffer in the 
init()-doFinal() case  that helped performance with large data sizes. 
The final result was a 1MB file is encrypted at 2GB/sec vs 250MB/sec.

This change is not meant to fix all possible performance bottlenecks.

http://cr.openjdk.java.net/~ascarpino/8201633/webrev/

Tony