Get rid of all the library tags.

test/snapshot/creates_a_snapshot_test.dart

 // Copyright (c) 2014, 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:path/path.dart' as p;
 import 'package:scheduled_test/scheduled_test.dart';
 
 import '../descriptor.dart' as d;
 import '../test_pub.dart';
 
 main() {
   integration("creates a snapshot for an immediate dependency's executables",
       () {
     servePackages((builder) {
@@ skipping 28 matching lines @@
 
     var process = pubRun(args: ['foo:hello']);
     process.stdout.expect("hello!");
     process.shouldExit();
 
     process = pubRun(args: ['foo:goodbye']);
     process.stdout.expect("goodbye!");
     process.shouldExit();
   });
 }