Adding issue link to valid uri comment
diff --git a/lib/shelf_static.dart b/lib/shelf_static.dart
index 41946b6..da47d7c 100644
--- a/lib/shelf_static.dart
+++ b/lib/shelf_static.dart
@@ -17,7 +17,7 @@
 
   return (Request request) {
     // TODO: expand these checks and/or follow updates to Uri class to be more
-    //       strict.
+    //       strict. https://code.google.com/p/dart/issues/detail?id=16081
     if (request.requestedUri.path.contains(' ')) {
       return new Response.forbidden('The requested path is invalid.');
     }