Get rid of all the library tags.

lib/src/lock_file.dart

 // Copyright (c) 2012, 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.lock_file;
-
 import 'dart:collection';
 
 import 'package:path/path.dart' as p;
 import 'package:package_config/packages_file.dart' as packages_file;
 import 'package:pub_semver/pub_semver.dart';
 import 'package:source_span/source_span.dart';
 import 'package:yaml/yaml.dart';
 
 import 'io.dart';
 import 'package.dart';
@@ skipping 195 matching lines @@
     });
 
     var data = {'sdk': sdkConstraint.toString(), 'packages': packageMap};
     return """
 # Generated by pub
 # See http://pub.dartlang.org/doc/glossary.html#lockfile
 ${yamlToString(data)}
 """;
   }
 }