matching on enum abstract around another enum gives `Incompatible pattern` error.

[ousado]

enum Ordering {
  EQ;
  LT;
  GT;
}

@:publicFields
enum abstract TriState(Ordering) from Ordering {
	var True = GT;
	var False = LT;
	var Both = EQ;

	function icon():Int {
		return switch (this : TriState) {
			case True:1;                  // Error: Incompatible pattern
			case False:2;
			case Both:3;
		}
	}
}

class Test {
	static function main() {
	}
}