Fix warnings_checker.dart handling of multitests

tests/language_strong/factory1_test.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.
 // Dart test program for testing factory generic result types.
 
 class A<T> {
   A() { }
   factory A.factory() {
     return new A<String>();
   }
 }
 
 class B<T> extends A<T> {
   B() { }
   factory B.factory() {
     return new B<String>();
   }
 }
 
 
 main() {
   new A<String>.factory();
-  new A<int>.factory(); // /// 00: dynamic type error
+  new A<int>.factory(); // //# 00: dynamic type error
   new B<String>.factory();
-  new B<int>.factory(); // /// 01: dynamic type error
+  new B<int>.factory(); // //# 01: dynamic type error
 }