Get rid of all the library tags.

test/serve/gets_first_if_dev_dependency_changed_test.dart

 // Copyright (c) 2013, 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 'dart:convert';
 
 import '../descriptor.dart' as d;
 import '../test_pub.dart';
 import 'utils.dart';
 
 main() {
   integration("gets first if a dev dependency has changed", () {
     d.dir("foo", [
       d.libPubspec("foo", "0.0.1"),
@@ skipping 12 matching lines @@
         'packages': {}
       }))
     ]).create();
 
     pubGet();
     pubServe();
     requestShouldSucceed("packages/foo/foo.dart", 'main() => "foo";');
     endPubServe();
   });
 }