RFR: 8240977: ProblemList failing jtreg tests on macos

[Philip Race]

https://bugs.openjdk.java.net/browse/JDK-8240977
Adding just one test that fails way too often  :-
diff --git a/test/jdk/ProblemList.txt b/test/jdk/ProblemList.txt
--- a/test/jdk/ProblemList.txt
+++ b/test/jdk/ProblemList.txt
@@ -121,6 +121,7 @@
 
java/awt/Focus/IconifiedFrameFocusChangeTest/IconifiedFrameFocusChangeTest.java 
6849364 generic-all
 java/awt/Focus/AutoRequestFocusTest/AutoRequestFocusToFrontTest.java 
6848406 generic-all
 java/awt/Focus/AutoRequestFocusTest/AutoRequestFocusSetVisibleTest.java 
6848407 generic-all
+java/awt/Focus/UnaccessibleChoice/AccessibleChoiceTest.java 8239801 
macosx-all
 java/awt/Frame/MaximizedUndecorated/MaximizedUndecorated.java 8022302 
generic-all
 java/awt/Frame/FrameLocation/FrameLocation.java 8233703 linux-all
 java/awt/FileDialog/FileDialogIconTest/FileDialogIconTest.java 8160558 
windows-all

-phil.