Fix warnings_checker.dart handling of multitests

tests/language_strong/getters_setters_type_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.
 // Getters and setters can have different types, but it is a warning if the
 // two types are not assignable.
 
 import "package:expect/expect.dart";
 
 int bar = 499;
 
-int // /// 01: static type warning
+int // //# 01: static type warning
 get foo => bar;
 
 void set foo(
-             String //  /// 01: continued
+             String //  //# 01: continued
              str) { bar = str.length; }
 
 main() {
   int x = foo;
   Expect.equals(499, x);
   foo = "1234";
   int y = foo;
   Expect.equals(4, y);
 }