Before this commit, we added Enum.entries only in case when
LanguageFeature.EnumEntries was ON (with an exception in K1/Java case).
In this commit we add Enum.entries unconditionally, and in case
the language feature is OFF we filter them out during tower resolve.
Before this commit, during the resolve of companion objects we used
the same context than for any nested class. However, during companion
object resolve we should not have companion object receiver itself
accessible in any case (in particular, it should not be accessible
in constructor). So in this commit we introduced separate context
for this purpose.