Fix errors in previous commit

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 959 matching lines @@
    * password. Alternatively the API [addProxyCredentials] can be used
    * to set credentials for proxies which require authentication.
    */
   static String findProxyFromEnvironment(Uri url,
                                          {Map<String, String> environment}) {
     return _HttpClient._findProxyFromEnvironment(url, environment);
   }
 
   /**
    * Sets the function to be called when a proxy is requesting
-   * authentication. The proxy used and and the security realm from
-   * the server are passed in the arguments [host], [port] and
-   * [realm].
+   * authentication. Information on the proxy in use and the security
+   * realm for the authentication are passed in the arguments [host],
+   * [port] and [realm].
    *
    * The function returns a [Future] which should complete when the
    * authentication has been resolved. If credentials cannot be
    * provided the [Future] should complete with [false]. If
    * credentials are available the function should add these using
    * [addProxyCredentials] before completing the [Future] with the value
    * [true].
    *
    * If the [Future] completes with [true] the request will be retried
    * using the updated credentials. Otherwise response processing will
@@ skipping 305 matching lines @@
 class RedirectLimitExceededException extends RedirectException {
   const RedirectLimitExceededException(List<RedirectInfo> redirects)
       : super("Redirect limit exceeded", redirects);
 }
 
 
 class RedirectLoopException extends RedirectException {
   const RedirectLoopException(List<RedirectInfo> redirects)
       : super("Redirect loop detected", redirects);
 }