Make dart:convert strong mode clean.

pkg/analysis_server/lib/src/channel/channel.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 channel;
 
 import 'dart:async';
 import 'dart:convert';
 
 import 'package:analysis_server/plugin/protocol/protocol.dart';
@@ skipping 67 matching lines @@
    * Send the given [request] to the server
    * and return a future with the associated [Response].
    */
   Future<Response> sendRequest(Request request);
 }
 
 /**
  * Instances of the class [JsonStreamDecoder] convert JSON strings to JSON
  * maps.
  */
-class JsonStreamDecoder extends
-    ChunkedConverter<String, Map, String, Map> {
+class JsonStreamDecoder extends Converter<String, Map> {
   @override
   Map convert(String text) => JSON.decode(text);
 
   @override
   ChunkedConversionSink<String> startChunkedConversion(Sink<Map> sink) =>
       new ChannelChunkSink<String, Map>(this, sink);
 }
 
 /**
  * Instances of the class [NotificationConverter] convert JSON maps to
  * [Notification]s.
  */
-class NotificationConverter extends
-    ChunkedConverter<Map, Notification, Map, Notification> {
+class NotificationConverter extends Converter<Map, Notification> {
   @override
   Notification convert(Map json) => new Notification.fromJson(json);
 
   @override
   ChunkedConversionSink<Map> startChunkedConversion(Sink<Notification> sink) =>
       new ChannelChunkSink<Map, Notification>(this, sink);
 }
 
 /**
  * Instances of the class [ResponseConverter] convert JSON maps to [Response]s.
  */
-class ResponseConverter extends
-    ChunkedConverter<Map, Response, Map, Response> {
+class ResponseConverter extends Converter<Map, Response> {
   @override
   Response convert(Map json) => new Response.fromJson(json);
 
   @override
   ChunkedConversionSink<Map> startChunkedConversion(Sink<Response> sink) =>
       new ChannelChunkSink<Map, Response>(this, sink);
 }
 
 /**
  * The abstract class [ServerCommunicationChannel] defines the behavior of
@@ skipping 19 matching lines @@
   /**
    * Send the given [notification] to the client.
    */
   void sendNotification(Notification notification);
 
   /**
    * Send the given [response] to the client.
    */
   void sendResponse(Response response);
 }