Big merge from experimental to bleeding edge.

pkg/http/lib/src/client.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 client;
 
+import 'dart:async';
 import 'dart:io';
 import 'dart:scalarlist';
 
 import 'base_client.dart';
 import 'base_request.dart';
 import 'io_client.dart';
 import 'streamed_response.dart';
 import 'response.dart';
 import 'utils.dart';
 
@@ skipping 72 matching lines @@
   Future<Uint8List> readBytes(url, {Map<String, String> headers});
 
   /// Sends an HTTP request and asynchronously returns the response.
   Future<StreamedResponse> send(BaseRequest request);
 
   /// Closes the client and cleans up any resources associated with it. It's
   /// important to close each client when it's done being used; failing to do so
   /// can cause the Dart process to hang.
   void close();
 }