RFR: JDK-8169872 incremental CMS always crashes VM

[Edward Nevill]

Looks good,

Thanks, Ed.

On Thu, 2016-11-17 at 13:18 +0000, Andrey Petushkov wrote:
> Dear All,
> 
> Could you please review the simple patch to fix the incremental CMS.
> Apparently the necessary check was forgotten at the fast path during
> backporting from jdk9, since the latter does not include iCMS
> 
> The problem could easily be reproduced by starting any Java
> application with the VM supplied the -Xincgc flag
> 
> issue: https://bugs.openjdk.java.net/browse/JDK-8169872
> webrev: http://cr.openjdk.java.net/~apetushkov/8169872/webrev/
> 
> Thanks,
> Andrey