Only use one timer to handle HttpServer::idleTimeout.

sdk/lib/io/http.dart

 // Copyright (c) 2013, 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.
 
 part of dart.io;
 
 /**
  * HTTP status codes.
  */
 abstract class HttpStatus {
@@ skipping 80 matching lines @@
    */
   String serverHeader;
 
   /**
    * Get or set the timeout used for idle keep-alive connections. If no further
    * request is seen within [idleTimeout] after the previous request was
    * completed, the connection is dropped.
    *
    * Default is 120 seconds.
    *
+   * Note that it may take up to `2 * idleTimeout` before a idle connection is
+   * aborted.
+   *
    * To disable, set [idleTimeout] to `null`.
    */
   Duration idleTimeout;
 
   /**
    * Starts listening for HTTP requests on the specified [address] and
    * [port].
    *
    * The [address] can either be a [String] or an
    * [InternetAddress]. If [address] is a [String], [bind] will
@@ skipping 1500 matching lines @@
 class RedirectException implements HttpException {
   final String message;
   final List<RedirectInfo> redirects;
 
   const RedirectException(this.message, this.redirects);
 
   String toString() => "RedirectException: $message";
 
   Uri get uri => redirects.last.location;
 }