Fix warnings_checker.dart handling of multitests

tests/language/bad_override_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.
 
 class Fisk {
   get fisk => null;     
-  static //           /// 01: static type warning       
+  static //           //# 01: static type warning       
   set fisk(x) {}
 
-  static //           /// 02: static type warning       
+  static //           //# 02: static type warning       
   get hest => null;     
   set hest(x) {}        
 
   foo() {}
   var field;
   method() {}
   nullary() {}
 }
 
 class Hest extends Fisk {
-  static foo() {} //  /// 03: compile-time error
-  field() {} //       /// 04: compile-time error
-  var method; //      /// 05: compile-time error
-  nullary(x) {} //    /// 06: static type warning
+  static foo() {} //  //# 03: compile-time error
+  field() {} //       //# 04: compile-time error
+  var method; //      //# 05: compile-time error
+  nullary(x) {} //    //# 06: static type warning
 }
 
 main() {
   new Fisk();
   new Hest();
 }