Signifies that the annotated functional type has the prefix of size
count for context receivers.
@ContextFunctionTypeParams(2) @ExtensionFunctionType Function4<String, Int, Double, Byte, Unit> is a normalized representation of
context(String, Int) Double.(Byte) -> Unit.
Just the same as @ExtensionFunctionType, this annotation is not assumed to be used in source code, preferring the explicit function type syntax, like in the example above.
There's no need in any additional opt-in limitations because this annotation might only be referenced by users
who turned on an experimental
-Xcontext-receivers compiler flag, for which there are no backward/forward compatibilities guarantees.