Fix warnings_checker.dart handling of multitests

tests/language/method_override3_test.dart

 // Copyright (c) 2013, 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';
 
 class A {
   foo(required1, { named1: 499}) => -(required1 + named1 * 3);
   bar(required1, required2, { named1: 13, named2: 17})
       => -(required1 + required2 * 3 + named1 * 5 + named2 * 7);
   gee({named1: 31}) => -named1;
 }
 
 class B extends A {
   foo(required1
-     /* // /// 00: static type warning
+     /* // //# 00: static type warning
       , { named1: 499 }
-     */ // /// 00: static type warning
+     */ // //# 00: static type warning
      ) {
     return required1;
   }
 
   bar(required1, required2,
       { named1: 13
-      /* // /// 01: static type warning
+      /* // //# 01: static type warning
         , named2: 17
-      */ // /// 01: static type warning
+      */ // //# 01: static type warning
       }) {
     return required1 + required2 * 3 + named1 * 5;
   }
 
   gee({named2: 11
-      /* // /// 02: static type warning
+      /* // //# 02: static type warning
        , named1: 31
-      */ // /// 02: static type warning
+      */ // //# 02: static type warning
       }) {
     return named2 * 99;
   }
 }
 
 main() {
   var b = new B();
   Expect.equals(499, b.foo(499));
   Expect.equals(1 + 3 * 3 + 5 * 5, b.bar(1, 3, named1: 5));
   Expect.equals(1 + 3 * 3 + 13 * 5, b.bar(1, 3));
   Expect.equals(3 * 99, b.gee(named2: 3));
   Expect.equals(11 * 99, b.gee());
 }