RFR(T) 8231376: Unproblem list compiler/unsafe/Unsafe{Off,On}HeapBooleanTest.java tests

[Ekaterina Pavlova]

Hi,

compiler/unsafe/Unsafe{Off,On}HeapBooleanTest.java are listed in test/hotspot/jtreg/ProblemList-graal.txt
However these test failures have been fixed as part of JDK-8186134.
The tests don't fail anymore and need to be removed from ProblemList-graal.txt.
Please review this tiny and trivial patch.

      JBS: https://bugs.openjdk.java.net/browse/JDK-8231376
   webrev: http://cr.openjdk.java.net/~epavlova//8231376/webrev.00/index.html
  testing: run compiler/unsafe/Unsafe{Off,On}HeapBooleanTest.java with Graal enabled

thanks,
-katya