Remove unspecified behavior from test.

tests/language/class_literal_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.
 
 import "package:expect/expect.dart";
 
 // Test class literal expressions.
 
 class Class {
   static fisk() => 42;
@@ skipping 34 matching lines @@
   Expect.throws(() { var x = Class.field; }, (e) => e is NoSuchMethodError);
   Expect.throws(() { foo(Class.method()); }, (e) => e is NoSuchMethodError);
   Expect.throws(() { foo(Class.field); }, (e) => e is NoSuchMethodError);
   Expect.throws(() { Class / 3; }, (e) => e is NoSuchMethodError);
   Expect.throws(() { Class += 3; }, (e) => e is NoSuchMethodError);
 
   // Verify that a class literal isn't a string literal.
   Expect.notEquals(Class, "Class");
    
   // Verify toString() works for class literals.
-  Expect.equals((Class).toString(), "Class");
+  Expect.isTrue((Class).toString() is String);
   var y = Class;
-  Expect.equals(y.toString(), "Class");
+  Expect.isTrue(y.toString() is String);
   
   Expect.throws(() { Class.toString(); }, (e) => e is NoSuchMethodError);
 }