RFR: 8154341: [TESTBUG] G1 stress test for humongous objects allocation

[Michail Chernov]

Hi,

Could I have a reviews for a new stress test for humongous objects 
allocation please?

http://cr.openjdk.java.net/~mchernov/8154341/webrev.00/
https://bugs.openjdk.java.net/browse/JDK-8154341

This test tries to fill available heap with humongous objects in 
multiple threads. Test expects that VM will not crash.

Tested in different nightly configurations.

Thanks
Michail