<@U0ANSGGVC> Totally missing `@NonNull`s are the h...

# intellij

[dsgryazin]

@kirillrakhman Totally missing `@NonNull`s are the headache platform types are to care of, because I can't inspect all the java code for @NonNull (And I shouldn't really do it because of OCP). I guess it'd be enough to look through only the places, where kotlin uses the java code with platform types and remove those NPE-generating platform types where needed.

@yole I don't like platform types😢 Hear my pain😊