RFR: [9] Fix Shenandoah non-PCH build

[Roman Kennke]

Am 14.03.2018 um 01:46 schrieb Zhengyu Gu:
> A simple fix:
> 
> Webrev:
> http://cr.openjdk.java.net/~zgu/shenandoah/sh-jdk9-non-PCH/webrev.00/
> 
> 
> Test:
> 
>   hotspot_gc_shenandoah (release + fastdebug)
> 
> 
> Thanks,
> 
> -Zhengyu

Ok