Get rid of all the library tags.

test/hosted/version_negotiation_test.dart

 // Copyright (c) 2012, 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 pub_tests;
-
 import 'package:scheduled_test/scheduled_server.dart';
 import 'package:scheduled_test/scheduled_test.dart';
 import 'package:shelf/shelf.dart' as shelf;
 
 import '../descriptor.dart' as d;
 import '../test_pub.dart';
 
 main() {
   forBothPubGetAndUpgrade((command) {
     integration('sends the correct Accept header', () {
@@ skipping 37 matching lines @@
           (request) => new shelf.Response(406));
 
       pub.shouldExit(1);
 
       pub.stderr.expect(emitsLines(
           "Pub 0.1.2+3 is incompatible with the current version of localhost.\n"
           "Upgrade pub to the latest version and try again."));
     });
   });
 }