Support connecting to HTTPS URL's through a proxy

sdk/lib/io/http_impl.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;
 
 // The close queue handles graceful closing of HTTP connections. When
 // a connection is added to the queue it will enter a wait state
 // waiting for all data written and possibly socket shutdown from
 // peer.
@@ skipping 2008 matching lines @@
             var socket = socketConnections.first._socket;
             if (!secure && socket is! SecureSocket) break;
             if (secure && socket is SecureSocket &&
                  _sendClientCertificate == socket.sendClientCertificate &&
                  _clientCertificate == socket.certificateName) break;
           }
           socketConnections.removeFirst()._close();
         }
       }
       if (socketConnections == null || socketConnections.isEmpty) {
-        Socket socket = secure ?
+        Socket socket = secure && proxy.isDirect ?
             new SecureSocket(connectHost,
                              connectPort,
                              sendClientCertificate: _sendClientCertificate,
                              certificateName: _clientCertificate) :
             new Socket(connectHost, connectPort);
         // Until the connection is established handle connection errors
         // here as the HttpClientConnection object is not yet associated
         // with the socket.
         socket.onError = (e) {
           proxyIndex++;
@@ skipping 290 matching lines @@
 
 
 class _RedirectInfo implements RedirectInfo {
   const _RedirectInfo(int this.statusCode,
                       String this.method,
                       Uri this.location);
   final int statusCode;
   final String method;
   final Uri location;
 }