[test] Speculative fix for failing WatchKit test.

Author: jrose-apple

validation-test/stdlib/WatchKit.swift

@@ -19,14 +19,16 @@ WatchKitTests.test("WKInterfaceController/reloadRootControllers(_:)") {
 
 // This is a very weak test, but we can't do better without spawning a GUI app.
 WatchKitTests.test("WKInterfaceController/presentController(_:)") {
-  var curried = WKInterfaceController.presentController
+  let curried = WKInterfaceController.presentController(_:)
   typealias ExpectedType =
     (WKInterfaceController) -> ([(name: String, context: AnyObject)]) -> Void
   let checkType: ExpectedType = curried
   _blackHole(checkType)
 
   // FIXME: can't write the following line: rdar://20985062
   // expectType(ExpectedType.self, &curried)
+
+  let curried2 = WKInterfaceController.presentController as ExpectedType
 }
 
 } // #available(iOS 8.2, *)