Get rid of all the library tags.

test/serve/web_socket/path_to_urls_errors_test.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS d.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 pub_tests;
-
 import 'package:json_rpc_2/error_code.dart' as rpc_error_code;
 import 'package:path/path.dart' as p;
 
 import '../../descriptor.dart' as d;
 import '../../test_pub.dart';
 import '../utils.dart';
 
 main() {
   // TODO(rnystrom): Split into independent tests.
   integration("pathToUrls errors on bad inputs", () {
@@ skipping 36 matching lines @@
     expectNotServed(p.join("..", "foo", "web", "foo.txt"));
 
     endPubServe();
   });
 }
 
 void expectNotServed(String path) {
   expectWebSocketError("pathToUrls", {"path": path}, NOT_SERVED,
       'Asset path "$path" is not currently being served.');
 }