RFR(XS): JDK-8071335 - gc/TestSmallHeap.java throw OOM

[Jesper Wilhelmsson]

Hi,

Please review this small change.

The test TestSmallHeap.java is designed to make sure we can run a tiny 
application in 2MB of heap (according to the documentation this should work). 
Unfortunately when adding a specific set of flags we get an OOME. (For details 
see the bug.)

The conclusion in the bug is to not run the test with -Xcomp. This change fixes 
that.

Bug: https://bugs.openjdk.java.net/browse/JDK-8071335
Webrev: http://cr.openjdk.java.net/~jwilhelm/8071335/webrev.00/

Thanks,
/Jesper