hg: jdk10/hs/hotspot: 8178095: Add GC stress test TestSystemGC

[erik.helin at oracle.com]

Changeset: 8543b9974a60
Author:    ehelin
Date:      2017-04-05 14:21 +0200
URL:       http://hg.openjdk.java.net/jdk10/hs/hotspot/rev/8543b9974a60

8178095: Add GC stress test TestSystemGC
Reviewed-by: dfazunen, mgerdin

+ test/gc/stress/systemgc/TestSystemGC.java
+ test/gc/stress/systemgc/TestSystemGCWithCMS.java
+ test/gc/stress/systemgc/TestSystemGCWithG1.java
+ test/gc/stress/systemgc/TestSystemGCWithParallel.java
+ test/gc/stress/systemgc/TestSystemGCWithSerial.java