RFR(XS): 8209743: [TESTBUG] java/lang/management/MemoryMXBean/LowMemoryTest2.sh fails with OutOfMemoryError running in CDS mode

[Calvin Cheung]

bug: https://bugs.openjdk.java.net/browse/JDK-8209743

The first 3 scenarios of the test failed with 
"java.lang.OutOfMemoryError: Metaspace" when running with CDS archive.
A simple fix is to increase the MaxMetaspaceSize from 16m to 32m.

bash-4.2$ hg diff 
test/jdk/java/lang/management/MemoryMXBean/LowMemoryTest2.sh
diff --git 
a/test/jdk/java/lang/management/MemoryMXBean/LowMemoryTest2.sh 
b/test/jdk/java/lang/management/MemoryMXBean/LowMemoryTest2.sh
--- a/test/jdk/java/lang/management/MemoryMXBean/LowMemoryTest2.sh
+++ b/test/jdk/java/lang/management/MemoryMXBean/LowMemoryTest2.sh
@@ -57,9 +57,9 @@
  # Also we set the max metaspace to 16MB - otherwise the test takes too
  # long to run.

-go -noclassgc -XX:MaxMetaspaceSize=16m -XX:+UseSerialGC LowMemoryTest2
-go -noclassgc -XX:MaxMetaspaceSize=16m -XX:+UseParallelGC LowMemoryTest2
-go -noclassgc -XX:MaxMetaspaceSize=16m -XX:+UseConcMarkSweepGC 
LowMemoryTest2
+go -noclassgc -XX:MaxMetaspaceSize=32m -XX:+UseSerialGC LowMemoryTest2
+go -noclassgc -XX:MaxMetaspaceSize=32m -XX:+UseParallelGC LowMemoryTest2
+go -noclassgc -XX:MaxMetaspaceSize=32m -XX:+UseConcMarkSweepGC 
LowMemoryTest2

  # Test class metaspace - might hit MaxMetaspaceSize instead if
  # UseCompressedClassPointers is off or if 32 bit.

Tested on linux, solaris, and macosx with the same vmoptions as in 
tier5. Also repeated the test 5 times on each platform.

thanks,
Calvin