Get rid of all the library tags.

test/serve/serves_web_and_test_dirs_by_default_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 '../descriptor.dart' as d;
 import '../test_pub.dart';
 import 'utils.dart';
 
 main() {
   integration("serves web/ and test/ dirs by default", () {
     d.dir(appPath, [
       d.appPubspec(),
       d.dir("web", [d.file("foo", "contents")]),
       d.dir("test", [d.file("bar", "contents")]),
       d.dir("example", [d.file("baz", "contents")])
     ]).create();
 
     pubGet();
     pubServe();
     requestShouldSucceed("foo", "contents", root: "web");
     requestShouldSucceed("bar", "contents", root: "test");
     requestShould404("baz", root: "web");
     endPubServe();
   });
 }