Fix warnings_checker.dart handling of multitests

tests/language_strong/static_parameter_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.
 
 foo(x
-    , static int y // /// 01: compile-time error
-    , final static y // /// 02: compile-time error
-    , {static y} // /// 03: compile-time error
-    , [static y] // /// 04: compile-time error
+    , static int y // //# 01: compile-time error
+    , final static y // //# 02: compile-time error
+    , {static y} // //# 03: compile-time error
+    , [static y] // //# 04: compile-time error
     ) {
 }
 
 class C {
   bar(x
-      , static int y // /// 05: compile-time error
-      , final static y // /// 06: compile-time error
-      , {static y} // /// 07: compile-time error
-      , [static y] // /// 08: compile-time error
+      , static int y // //# 05: compile-time error
+      , final static y // //# 06: compile-time error
+      , {static y} // //# 07: compile-time error
+      , [static y] // //# 08: compile-time error
       ) {
   }
 
   static baz(x
-      , static int y // /// 09: compile-time error
-      , final static y // /// 10: compile-time error
-      , {static y} // /// 11: compile-time error
-      , [static y] // /// 12: compile-time error
+      , static int y // //# 09: compile-time error
+      , final static y // //# 10: compile-time error
+      , {static y} // //# 11: compile-time error
+      , [static y] // //# 12: compile-time error
       ) {
   }
 }
 
 main() {
   foo(1
-      , 1 // /// 01: continued
-      , 1 // /// 02: continued
-      , y: 1 // /// 03: continued
-      , 1 // /// 04: continued
+      , 1 // //# 01: continued
+      , 1 // //# 02: continued
+      , y: 1 // //# 03: continued
+      , 1 // //# 04: continued
       );
   new C().bar(1
-      , 1 // /// 05: continued
-      , 1 // /// 06: continued
-      , y: 1 // /// 07: continued
-      , 1 // /// 08: continued
+      , 1 // //# 05: continued
+      , 1 // //# 06: continued
+      , y: 1 // //# 07: continued
+      , 1 // //# 08: continued
       );
   C.baz(1
-      , 1 // /// 09: continued
-      , 1 // /// 10: continued
-      , y: 1 // /// 11: continued
-      , 1 // /// 12: continued
+      , 1 // //# 09: continued
+      , 1 // //# 10: continued
+      , y: 1 // //# 11: continued
+      , 1 // //# 12: continued
       );
 }