hg: shenandoah/jdk: Fix TestFullGCALot test failure

[zgu at redhat.com]

Changeset: a011d6f7f286
Author:    zgu
Date:      2018-06-01 19:18 -0400
URL:       http://hg.openjdk.java.net/shenandoah/jdk/rev/a011d6f7f286

Fix TestFullGCALot test failure

! src/hotspot/share/gc/shenandoah/shenandoahControlThread.cpp
! test/hotspot/jtreg/TEST.groups
! test/hotspot/jtreg/gc/TestFullGCALot.java