hg: jdk9/hs: 8154096: Extend WhiteBox API with methods which retrieve from VM information about available GC

[dmitry.fazunenko at oracle.com]

Changeset: 112989d7c3c0
Author:    dfazunen
Date:      2016-05-30 19:39 +0400
URL:       http://hg.openjdk.java.net/jdk9/hs/rev/112989d7c3c0

8154096: Extend WhiteBox API with methods which retrieve from VM information about available GC
Reviewed-by: kbarrett, iignatyev

! test/lib/sun/hotspot/WhiteBox.java
+ test/lib/sun/hotspot/gc/GC.java