Fix frog build

tests/language/src/PseudoKWTest.dart

 // Copyright (c) 2012, 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.
 // Check that we can use pseudo keywords as names in function level code.
 
 
 class PseudoKWTest {
   static testMain() {
 
     // This is a list of built-in identifiers from the Dart spec.
@@ skipping 39 matching lines @@
 }
 
 typedef(x) => "typedef " + x;
 
 static(abstract) {
   return abstract == true;
 }
 
 class A {
   var typedef = 0;
+  final operator = "smooth";
+
   set(x) { typedef = x; }
   get() => typedef - 5;
 
   static static() {
     return 1;
   }
   static check() {
     var o = new A();
     o.set(55);
     Expect.equals(50, o.get());
@@ skipping 21 matching lines @@
   PseudoKWTest.testMain();
   A.check();
   new B().static();
   Expect.equals(1, new B().operator());
   Expect.equals(1, A.static());
   typedef("T");
   Expect.equals("typedef T", typedef("T"));
   static("true");
   Expect.equals(false, static("true"));
 }