Get rid of all the library tags.

test/descriptor/packages.dart

 // Copyright (c) 2013, 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.
 
 /// Pub-specific scheduled_test descriptors.
-library descriptor.packages_file;
-
 import "dart:io" show File;
 import "dart:async" show Future;
 import "dart:convert" show UTF8;
 
 import 'package:package_config/packages_file.dart' as packages_file;
 import 'package:path/path.dart' as p;
 import 'package:scheduled_test/descriptor.dart';
 import 'package:scheduled_test/scheduled_test.dart';
 
 import '../test_pub.dart';
@@ skipping 88 matching lines @@
       for (var key in map.keys) {
         if (!_dependencies.containsKey(key)) {
           fail(".packages file contains unexpected entry: $key");
         }
       }
     }
   }
 
   String describe() => name;
 }