RFR(S): 8132715: Add tests which check that no allocations allowed in any of humongous regions​

[Kirill Zhaldybin]

Dear all,

Could please review this test for 8132715?

The test fills heap with humongous objects with a lot of wasted space, 
then starts to allocate non-humongous objects and checks that no 
allocations happened in humongous regions.
There are 3 runs of the test: with filled 10%, 50% and 80% of heap.

CR: https://bugs.openjdk.java.net/browse/JDK-8132715
WebRev: http://cr.openjdk.java.net/~kzhaldyb/webrevs/JDK-8132715/webrev.01/

Thank you.

Regards, Kirill