Get rid of all the library tags.

test/serve/supports_user_defined_lazy_transformers_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("supports a user-defined lazy transformer", () {
     serveBarback();
 
     d.dir(appPath, [
       d.pubspec({
@@ skipping 14 matching lines @@
     // The build should complete without the transformer logging anything.
     server.stdout.expect('Build completed successfully');
 
     requestShouldSucceed("foo.out", "foo.out");
     server.stdout.expect(emitsLines(
         '[Info from LazyRewrite]:\n'
         'Rewriting myapp|web/foo.txt.'));
     endPubServe();
   });
 }