RFR(S) 8151633: Don't keep copies of the survivor lists and counts in the G1CollectorPolicy

[Thomas Schatzl]

Hi Mikael,

On Thu, 2016-03-10 at 16:40 +0100, Mikael Gerdin wrote:
> Hi all,
> 
> G1CollectorPolicy contains copies of the linked list heads and tails 
> present in YoungList.
> In order to reduce the size of the G1CollectorPolicy, I suggest we 
> remove them and have the policy access the ones in YoungList instead.
> 
> Webrev: http://cr.openjdk.java.net/~mgerdin/8151633/webrev.0/
> Bug: https://bugs.openjdk.java.net/browse/JDK-8151633
> Testing: JPRT (including runs with assertions that the pointers and 
> lenght are in fact equal)

  looks good.

Thomas