Introduce class Sink<T>.

pkg/analysis_server/lib/src/channel.dart

Index: pkg/analysis_server/lib/src/channel.dart
diff --git a/pkg/analysis_server/lib/src/channel.dart b/pkg/analysis_server/lib/src/channel.dart
index 85203b0bdab74a0c8dcca61d6d644c892d57344b..7fcaa12c0e571b7aaf6da40bfd0fee1c8753eb29 100644
--- a/pkg/analysis_server/lib/src/channel.dart
+++ b/pkg/analysis_server/lib/src/channel.dart
@@ -178,7 +178,7 @@ class _JsonStreamDecoder extends Converter<String, Map> {
   Map convert(String text) => JSON.decode(text);
 
   @override
-  ChunkedConversionSink startChunkedConversion(ChunkedConversionSink sink) =>
+  ChunkedConversionSink startChunkedConversion(Sink sink) =>
       new _ChannelChunkSink<String, Map>(this, sink);
 }
 
@@ -191,7 +191,7 @@ class _ResponseConverter extends Converter<Map, Response> {
   Response convert(Map json) => new Response.fromJson(json);
 
   @override
-  ChunkedConversionSink startChunkedConversion(ChunkedConversionSink sink) =>
+  ChunkedConversionSink startChunkedConversion(Sink sink) =>
       new _ChannelChunkSink<Map, Response>(this, sink);
 }
 
@@ -204,27 +204,27 @@ class _NotificationConverter extends Converter<Map, Notification> {
   Notification convert(Map json) => new Notification.fromJson(json);
 
   @override
-  ChunkedConversionSink startChunkedConversion(ChunkedConversionSink sink) =>
+  ChunkedConversionSink startChunkedConversion(Sink sink) =>
       new _ChannelChunkSink<Map, Notification>(this, sink);
 }
 
 /**
- * A [_ChannelChunkSink] uses a [Convter] to translate chunks.
+ * A [_ChannelChunkSink] uses a [Converter] to translate chunks.
  */
 class _ChannelChunkSink<S, T> extends ChunkedConversionSink<S> {
   final Converter<S, T> _converter;
-  final ChunkedConversionSink _chunkedSink;
+  final Sink _sink;
 
-  _ChannelChunkSink(this._converter, this._chunkedSink);
+  _ChannelChunkSink(this._converter, this._sink);
 
   @override
   void add(S chunk) {
     var convertedChunk = _converter.convert(chunk);
     if (convertedChunk != null) {
-      _chunkedSink.add(convertedChunk);
+      _sink.add(convertedChunk);
     }
   }
 
   @override
-  void close() => _chunkedSink.close();
+  void close() => _sink.close();
 }