RFR(S): 8151637: Move CollectionSetChooser rebuild code into CollectionSetChooser

[Thomas Schatzl]

Hi Mikael,

On Mon, 2016-03-14 at 12:07 +0100, Mikael Gerdin wrote:
> Hi all,
> 
> Currently when the CSetChooser needs to be injected with new regions
> the 
> collector policy is responsible for calling a bunch of semi internal 
> functions on the chooser and setting up some closures which are only 
> relevant to the cset chooser.
> I've moved that code into the collection set chooser instead.
> 
> I wasn't entirely clear on how the API for rebuild() should look
> since 
> under the hood the closures go and access the G1CollectedHeap
> instance 
> through the static in order to access the heap iteration method but 
> since that has not changed in this patch I've left it as is.
> 
> Bug: https://bugs.openjdk.java.net/browse/JDK-8151637
> Webrev: http://cr.openjdk.java.net/~mgerdin/8151637/webrev.0/
> Testing: JPRT

  looks good.

Maybe the moved closure code (closure naming, g1 prefix, camelcase
member names, make ParKnownGarbageHRClosure a local class to the task,
etc) could be touched up a little.

Feel free to ignore though.

Thanks,
  Thomas