RFR: Use CollectedHeap::base() instead of ShenandoahHeap::first_region_bottom()

[Aleksey Shipilev]

On 04/24/2017 05:34 PM, Roman Kennke wrote:
> I found that CollectedHeap has a base() method which seems identical to
> ShenandoahHeap::first_region_bottom(). This patch changes all uses of
> the latter to the former. Ok?
> 
> http://cr.openjdk.java.net/~rkennke/heapbase/webrev.00/

Yes.

-Aleksey