Change dart2js_foreign suite to use metadata.

dart/tests/compiler/dart2js_foreign/native_class_inheritance4_test.dart

 // Copyright (c) 2011, 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.
 
 // Additional Dart code may be 'placed on' hidden native classes.  With
 // inheritance, the superclass method must not be reached by a call on the
 // subclass.
 
-class A native "*A" {
+@native("*A")
+class A  {
   var _field;
 
   int get X => _field;
   void set X(int x) { _field = x; }
 
   int method(int z) => _field + z;
 }
 
-class B extends A native "*B" {
+@native("*B")
+class B extends A  {
   var _field2;
 
   int get X => _field2;
   void set X(int x) { _field2 = x; }
 
   int method(int z) => _field2 + z;
 }
 
-A makeA() native { return new A(); }
-B makeB() native { return new B(); }
+@native A makeA() { return new A(); }
+@native B makeB() { return new B(); }
 
-void setup() native @"""
+@native(@"""
 function inherits(child, parent) {
   if (child.prototype.__proto__) {
     child.prototype.__proto__ = parent.prototype;
   } else {
     function tmp() {};
     tmp.prototype = parent.prototype;
     child.prototype = new tmp();
     child.prototype.constructor = child;
   }
 }
 
 function A(){}
 function B(){}
 inherits(B, A);
 makeA = function(){return new A;};
 makeB = function(){return new B;};
-""";
+""")
+void setup();
 
 testBasicA_dynamic() {
   setup();  // Fresh constructors.
 
   var a = [makeA()][0];
 
   a.X = 100;
   Expect.equals(100, a._field);
   Expect.equals(100, a.X);
   Expect.equals(150, a.method(50));
@@ skipping 78 matching lines @@
 }
 
 main() {
   testBasicA_dynamic();
   testBasicA_typed();
   testBasicB_dynamic();
   testBasicB_typed();
   testAB_dynamic();
   testAB_typed();
 }