RFR 8186089: Move Arena to its own header file

[coleen.phillimore at oracle.com]

Harold,

This looks great!  Thank you for doing this.

Coleen

On 8/15/17 9:43 AM, harold seigel wrote:
> Hi,
>
> Please review this JDK-10 change to move class Arena into its own 
> header file for reasons described in the bug.
>
> Note that since the SA doesn't use class Chunk, it need no longer be 
> exported to it.  Also, class Chunk is in the new arena.hpp header file 
> (as opposed to just the .cpp file) because class HandleMark uses it in 
> handles.hpp.
>
> Open Webrev: 
> http://cr.openjdk.java.net/~hseigel/bug_8186089/webrev/index.html
>
> JBS Bug: https://bugs.openjdk.java.net/browse/JDK-8186089
>
> The change was tested with the JCK Lang and VM tests, the JTreg 
> hotspot, java/io, java/lang, java/util, and other tests, the 
> co-located NSK tests, JPRT, and with RBT tier2 - tier5 tests.
>
> Thanks, Harold
>