Get rid of all the library tags.

lib/src/util/path_handler.dart

 // Copyright (c) 2015, 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.util.path_handler;
-
 import 'package:path/path.dart' as p;
 import 'package:shelf/shelf.dart' as shelf;
 
 /// A handler that routes to sub-handlers based on exact path prefixes.
 class PathHandler {
   /// A trie of path components to handlers.
   final _paths = new _Node();
 
   /// The shelf handler.
   shelf.Handler get handler => _onRequest;
@@ skipping 30 matching lines @@
     return handler(request.change(
         path: p.url.joinAll(components.take(handlerIndex + 1))));
   }
 }
 
 /// A trie node.
 class _Node {
   shelf.Handler handler;
   final children = new Map<String, _Node>();
 }