[9] Review request: 8169555: Need unit tests for JDK-8169289

[Kevin Rushforth]

Dave and Dave,

Please review:
https://bugs.openjdk.java.net/browse/JDK-8169555
http://cr.openjdk.java.net/~kcr/8169555/webrev.00/

This adds three new unit tests for verifying that we can launch modular 
FX applications.

-- Kevin