If a type paramter is not reified or nullable, different errors will
be reported by FirGetClassCallChecker.
When determining whether type parameter wrapped in qualified access is a
standalone expression or not, we examine whether the checker context has
other qualified accesses in stack. Class literals (::class) is desugared
to FirGetClassCall, and thus not stacked as qualified access. Since
class literals are a special type of callable reference (a subtype of
qualified access), we should keep track of FirGetClassCall in a similar
way.
Dmitriy Novozhilov