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

tests/compiler/dart2js_native/subclassing_super_call_test.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 import "native_testing.dart";
 import 'dart:_js_helper' show setNativeSubclassDispatchRecord;
 import 'dart:_interceptors'
     show findInterceptorForType, findConstructorForNativeSubclassType;
 
 // Test for super access from classes that extend native classes.
@@ skipping 24 matching lines @@
   get afield => super.afield;
   set afield(value) => super.afield = value;
   afun() => super.afun();
 }
 
 BB makeBB() native;
 
 @Creates('=Object')
 getBBPrototype() native;
 
-void setup() native r"""
-function N2() {}
-N2.prototype.foo = function() { return "foo:" + this.text; }
-function BB() {}
-BB.prototype.__proto__ = N2.prototype;
-makeBB = function(){return new BB;};
+void setup() {
+  JS('', r"""
+(function(){
+  function N2() {}
+  N2.prototype.foo = function() { return "foo:" + this.text; };
+  function BB() {}
+  BB.prototype.__proto__ = N2.prototype;
+  makeBB = function(){return new BB()};
 
-getBBPrototype = function(){return BB.prototype;};
-""";
+  getBBPrototype = function(){return BB.prototype;};
+})()""");
+}
 
 testSuperOnNative() {
   BB b1 = makeBB();
   BB b2 = makeBB();
 
   var constructor = findConstructorForNativeSubclassType(BB, 'init');
   Expect.isNotNull(constructor);
   JS('', '#(#)', constructor, b1);
   JS('', '#(#)', constructor, b2);
 
@@ skipping 58 matching lines @@
 
 main() {
   nativeTesting();
   setup();
 
   setNativeSubclassDispatchRecord(getBBPrototype(), findInterceptorForType(BB));
 
   testSuperOnNative();
   testSuperOnSubclassOfNative();
 }