Use boxMethod and unboxMethod for Unit

Author: nicolasstucki

compiler/src/dotty/tools/dotc/transform/Erasure.scala

@@ -477,7 +477,7 @@ object Erasure {
 	 */
     override def typedApply(tree: untpd.Apply, pt: Type)(implicit ctx: Context): Tree = {
       val Apply(fun, args) = tree
-      if (fun.symbol == defn.cbnArg || (tree.symbol.name == nme.box || tree.symbol.name == nme.unbox) && tree.symbol.owner.asClass.companionClass == defn.UnitClass)
+      if (fun.symbol == defn.cbnArg || fun.symbol == boxMethod(defn.UnitClass) || fun.symbol == unboxMethod(defn.UnitClass))
         typedUnadapted(args.head, pt)
       else typedExpr(fun, FunProto(args, pt, this)) match {
         case fun1: Apply => // arguments passed in prototype were already passed