dart2js_native tests: Migrate 'native STRING' to JS-calls - part 2/2

tests/compiler/dart2js_native/subclassing_2_test.dart

Index: tests/compiler/dart2js_native/subclassing_2_test.dart
diff --git a/tests/compiler/dart2js_native/subclassing_2_test.dart b/tests/compiler/dart2js_native/subclassing_2_test.dart
index ae56d636adbff89857c54f137d71a4dde140fcd8..66c8d680751c0fd1c0ab1c0a08706ae96231ceb7 100644
--- a/tests/compiler/dart2js_native/subclassing_2_test.dart
+++ b/tests/compiler/dart2js_native/subclassing_2_test.dart
@@ -27,14 +27,17 @@ B makeB() native;
 @Creates('=Object')
 getBPrototype() native;
 
-void setup() native r"""
-function A() {}
-function B() {}
-makeA = function(){return new A;};
-makeB = function(){return new B;};
-
-getBPrototype = function(){return B.prototype;};
-""";
+void setup() {
+  JS('', r"""
+(function(){
+  function A() {}
+  function B() {}
+  makeA = function(){return new A()};
+  makeB = function(){return new B()};
+
+  getBPrototype = function(){return B.prototype;};
+})()""");
+}
 
 main() {
   nativeTesting();