RFR: Fix Shenandoah build issues

[Zhengyu Gu]

A few similar build issues as Shenandoah jdk8u, mainly on Windows.

Shenandoah JDK: 
http://cr.openjdk.java.net/~zgu/shenandoah/sh-jdk-build/webrev.00/

Shenandoah JDK10: 
http://cr.openjdk.java.net/~zgu/shenandoah/sh-jdk10-build/webrev.00/

Shenandoah JDK9: 
http://cr.openjdk.java.net/~zgu/shenandoah/sh-jdk9-build/webrev.00/

Test:

  Built on Windows 64 and Linux 64

Thanks,

-Zhengyu