The modality was nondeterministic before.
The main change sits in OverrideResolver: the logic of "fake override" generation is restructured so that
all the descriptors a newly created "fake" one overrides are known by the time it is created, so its
modality can be determined properly from their modalities.
Also, the ReadJavaBinaryClassTestGenerated is now a clear JUnit3 test case
Andrey Breslav