RFR 8223593 : Refactor code for reallocating storage

[Pavel Rappo]

> On 10 May 2019, at 15:41, Roger Riggs <Roger.Riggs at oracle.com> wrote:
> 
> 98:  I think you've dropped the normal doubling of the buffer size that comes from old line 115.
>   The buffer should be doubling in size, but at least minsize.

I thought about it too initially. But then I reproduced that function. It seemed
to be doing the right thing. What it boils down to is this:

    oldCapacity + oldCapacity

In other words, doubling in size, as required. Or am I missing something?

> PriorityQueue.java is part of JSR 166 and the changes should be done upstream or deferred due to adding a dependency on a JDK 13 API.

I understand that. First, ArraysSupport changes, then JSR 166 changes, finally
JDK gets that last change from the JSR 166 repo.

Thanks Roger.