Fix warnings_checker.dart handling of multitests

tests/language_strong/constructor_redirect2_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.
 // Redirection constructors must not have a function body.
 
 class A {
   var x;
   A(this.x) {}
 
   // Redirecting constructor must not have a function body.
-  A.illegalBody(x) : this(3) {} //     /// 01: compile-time error
+  A.illegalBody(x) : this(3) {} //     //# 01: compile-time error
 
   // Redirecting constructor must not initialize any fields.
-  A.illegalInit() : this(3), x = 5; // /// 02: compile-time error
+  A.illegalInit() : this(3), x = 5; // //# 02: compile-time error
 
   // Redirecting constructor must not have initializing formal parameters.
-  A.illegalFormal(this.x) : this(3); // /// 03: compile-time error
+  A.illegalFormal(this.x) : this(3); // //# 03: compile-time error
 
   // Redirection constructors must not call super constructor.
-  A.illegalSuper() : this(3), super(3); // /// 04: compile-time error
+  A.illegalSuper() : this(3), super(3); // //# 04: compile-time error
 }
 
 main() {
   new A(3);
-  new A.illegalBody(10); //        /// 01: continued
-  new A.illegalInit(10); //        /// 02: continued
-  new A.illegalFormal(10); //      /// 03: continued
-  new A.illegalSuper(10); //       /// 04: continued
+  new A.illegalBody(10); //        //# 01: continued
+  new A.illegalInit(10); //        //# 02: continued
+  new A.illegalFormal(10); //      //# 03: continued
+  new A.illegalSuper(10); //       //# 04: continued
 }