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

tests/compiler/dart2js_native/subclassing_super_call_test.dart

Index: tests/compiler/dart2js_native/subclassing_super_call_test.dart
diff --git a/tests/compiler/dart2js_native/subclassing_super_call_test.dart b/tests/compiler/dart2js_native/subclassing_super_call_test.dart
index a94c01bf32d77e9d689a417a17be577b38371a49..61e3fc155c9b1a5a7cd3d3c0e34e7f464744826a 100644
--- a/tests/compiler/dart2js_native/subclassing_super_call_test.dart
+++ b/tests/compiler/dart2js_native/subclassing_super_call_test.dart
@@ -42,15 +42,18 @@ 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;};
-
-getBBPrototype = function(){return BB.prototype;};
-""";
+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;};
+})()""");
+}
 
 testSuperOnNative() {
   BB b1 = makeBB();