[JS IR BE] fix default arguments lowering

js/js.translator/testData/box/defaultArguments/enumWithDefArg.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JS_IR
 // EXPECTED_REACHABLE_NODES: 1291
 package foo
 
@@ -7,9 +6,14 @@ enum class A(val a: Int = 1) {
     SECOND(2)
 }
 
+class B(val a: Int = 1)
+
 fun box(): String {
     if (A.FIRST.a == 1 && A.SECOND.a == 2) {
         return "OK"
     }
+
+    B()
+
     return "fail"
 }