Handle exception cause with null message #5146
The handling of exc exceptions in the jsr223 JRubyEngine assumes that all exceptions have causes, and that the cause has a non-null message. This is not always the case and results in a NullPointerException without the original exception.
I added a test for the two cases I know of.
I noticed that all the other tests for the jsr223 JRubyEngine are disabled. Any reason for that?