Flush analysis server output stream when closed.

pkg/analysis_server/lib/src/channel/byte_stream_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.byte_stream;
 
 import 'dart:async';
 import 'dart:convert';
 import 'dart:io';
 
@@ skipping 62 matching lines @@
 
   /**
    * Future that will be completed when the input stream is closed.
    */
   Future get closed {
     return _closed.future;
   }
 
   @override
   void close() {
-    if (!_closed.isCompleted) {
-      _closed.complete();
-    }
+    output.flush().then((_) {
+      if (!_closed.isCompleted) {
+        _closed.complete();
+      }
+    });
   }
 
   @override
   void listen(void onRequest(Request request), {Function onError, void
       onDone()}) {
     input.transform((new Utf8Codec()).decoder).transform(new LineSplitter()
         ).listen((String data) => _readRequest(data, onRequest), onError: onError,
         onDone: () {
       close();
       onDone();
@@ skipping 40 matching lines @@
     ServerCommunicationChannel.FromJson.start();
     Request request = new Request.fromString(data);
     ServerCommunicationChannel.FromJson.stop();
     if (request == null) {
       sendResponse(new Response.invalidRequestFormat());
       return;
     }
     onRequest(request);
   }
 }