pkg: analysis aided cleanup

pkg/serialization/lib/serialization.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.
 
 /**
  * This provides a general-purpose serialization facility for Dart objects. A
  * [Serialization] is defined in terms of [SerializationRule]s and supports
  * reading and writing to different formats.
  *
  * ## Installing ##
@@ skipping 189 matching lines @@
  *       ..addRuleFor(new Person(), constructorFields: ["name"])
  *       ..namedObjects['Person'] = reflect(new Person()).type;
  *
  * [pub]: http://pub.dartlang.org
  * [pkg]: http://pub.dartlang.org/packages/serialization
  */
 library serialization;
 
 import 'src/mirrors_helpers.dart';
 import 'src/serialization_helpers.dart';
-import 'dart:async';
-import 'dart:json' as json;
 import 'dart:collection';
 
 part 'src/reader_writer.dart';
 part 'src/serialization_rule.dart';
 part 'src/basic_rule.dart';
 part 'src/format.dart';
 
 /**
  * This class defines a particular serialization scheme, in terms of
  * [SerializationRule] instances, and supports reading and writing them.
@@ skipping 275 matching lines @@
 }
 
 /**
  * An exception class for errors during serialization.
  */
 class SerializationException implements Exception {
   final String message;
   const SerializationException(this.message);
   String toString() => "SerializationException($message)";
 }