Minor. Formatting

libraries/stdlib/src/kotlin/OrderingJVM.kt

@@ -70,7 +70,7 @@ private class Function2Comparator<T>(val compareFn: (T,T) -> Int):  Comparator<T
 
     public override fun compare(a: T, b: T): Int {
         if (a === b) return 0
-        if (a == null) return - 1
+        if (a == null) return -1
         if (b == null) return 1
         return (compareFn)(a, b)
     }