RFR: 8150419: Cleanup BufferNode API

[Kim Barrett]

> On Feb 23, 2016, at 11:37 AM, Derek White <derek.white at oracle.com> wrote:
> 
> Looks good!
> 
> - Derek

Thanks, Derek.

> 
> On 2/22/16 8:24 PM, Kim Barrett wrote:
>> Please review this cleanup of the BufferNode API, which is part of
>> G1's PtrQueue facility.
>> 
>> CR:
>> https://bugs.openjdk.java.net/browse/JDK-8150419
>> 
>> Webrev:
>> http://cr.openjdk.java.net/~kbarrett/8150419/
>> 
>> Testing:
>> JPRT