The problem is very subtle (see the test): when generating a signature
for an object literal we also were mapping its super-class
(a type alias here).
Although we did unwrap its underlying constructor to map it properly
we did too late (after obtaining value parameters from the type alias constructor descriptor).
Another problem is that TypeAliasConstructorDescriptor.getOriginal
in the case does return itself, while it's expected to return
unsubstituted version
Note: everything works for common calls for such constructors
because they mapped through mapCallableMethod which contains
another custom unwrapping of type alias constructors
#KT-16555 Fixed
Denis Zharkov
2b21280ba9