The JavaFX unit tests have relied on a "mixed" class path for testing, needing to run on the application classpath to access Junit as well the test classes. This is not how Javafx runs in normal circumstances, as it is normally on the extension class loader.

We need to refactor these test:
    the "white box", classes that must reside in certain classes for protected class access
    the "black box": classes that can operate from outside the javafx package structure

This will require adding some "shims" in the white box, to allow the black box tests to operate.
All Junit tests must be in the black box.

All black box tests will be refactored into a package tests.*

This refactoring affects modularization efforts in JDK 9