Add unique serial numbers to sample X509 certificates. Remove the "sendClientCertificate" parameter…

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;
 
 const int _OUTGOING_BUFFER_SIZE = 8 * 1024;
 
 class _HttpIncoming extends Stream<List<int>> {
   final int _transferLength;
@@ skipping 1618 matching lines @@
       return completer.future;
     }
     var currentBadCertificateCallback = client._badCertificateCallback;
     callback(X509Certificate certificate) =>
         currentBadCertificateCallback == null ? false :
         currentBadCertificateCallback(certificate, uriHost, uriPort);
     Future socketFuture = (isSecure && proxy.isDirect
         ? SecureSocket.connect(host,
                                port,
                                context: context,
-                               sendClientCertificate: true,
                                onBadCertificate: callback)
         : Socket.connect(host, port));
     _connecting++;
     return socketFuture.then((socket) {
         _connecting--;
         socket.setOption(SocketOption.TCP_NODELAY, true);
         var connection =
             new _HttpClientConnection(key, socket, client, false, context);
         if (isSecure && !proxy.isDirect) {
           connection._dispose = true;
@@ skipping 1214 matching lines @@
   const _RedirectInfo(this.statusCode, this.method, this.location);
 }
 
 String _getHttpVersion() {
   var version = Platform.version;
   // Only include major and minor version numbers.
   int index = version.indexOf('.', version.indexOf('.') + 1);
   version = version.substring(0, index);
   return 'Dart/$version (dart:io)';
 }