TEST: convertion unit tests into run tests

backend.native/tests/codegen/branching/advanced_when5.kt

@@ -7,4 +7,8 @@ fun advanced_when5(i: Int): Int {
     4 -> { val v = 42; return v}
     else -> return 24
   }
+}
+
+fun main(args: Array<String>) {
+  if (advanced_when5(5) != 24) throw Error()
 }