Fix warnings_checker.dart handling of multitests

tests/lib/mirrors/generics_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.
 
 library test.type_arguments_test;
 
 import 'dart:mirrors';
 
 import 'package:expect/expect.dart';
 import 'generics_helper.dart';
 
 class A<T> {}
 class Z<T> {}
 class B extends A {}
 class C
-    extends A<num, int> // /// 01: static type warning
+    extends A<num, int> // //# 01: static type warning
     {}
 class D extends A<int> {}
 class E<S> extends A<S> {}
 class F<R> extends A<int> {}
 class G {}
 class H<A,B,C> {}
 class I extends G {}
 
 main() {
   // Declarations.
@@ skipping 126 matching lines @@
     });
   });
 
   Expect.equals(reflectClass(A).typeVariables[0].owner, reflectClass(A));
   Expect.equals(reflectClass(Z).typeVariables[0].owner, reflectClass(Z));
   Expect.notEquals(reflectClass(A).typeVariables[0],
                    reflectClass(Z).typeVariables[0]);
   Expect.equals(reflectClass(A).typeVariables[0],
                 reflectClass(A).typeVariables[0]);
 }