SPRINGFIELD — For nearly a year, three Illinois workers and two public worker unions waited for the U.S. Supreme Court to weigh in on a carbon copy of their union-fee dispute.Whatever result was crafted by the nation’s top justices in Friedrichs v. California Teachers Association, the lawyer who represented the workers said at the time the ruling “will almost certainly control what happens in our case.”But the death of Justice Antonin G. Scalia caused a 4-4 split on the issue of whether mandatory …