Don't add ':443' to host header, when the connection is secure.

sdk/lib/io/http_headers.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;
 
 class _HttpHeaders implements HttpHeaders {
   final Map<String, List<String>> _headers;
   final String protocolVersion;
 
   bool _mutable = true;  // Are the headers currently mutable?
   List<String> _noFoldingHeaders;
 
   int _contentLength = -1;
   bool _persistentConnection = true;
   bool _chunkedTransferEncoding = false;
   String _host;
   int _port;
 
-  _HttpHeaders(this.protocolVersion)
-      : _headers = new HashMap<String, List<String>>() {
+  final int _defaultPortForScheme;
+
+  _HttpHeaders(this.protocolVersion,
+               {int defaultPortForScheme: HttpClient.DEFAULT_HTTP_PORT})
+      : _headers = new HashMap<String, List<String>>(),
+        _defaultPortForScheme = defaultPortForScheme {
     if (protocolVersion == "1.0") {
       _persistentConnection = false;
     }
   }
 
   List<String> operator[](String name) => _headers[name.toLowerCase()];
 
   String value(String name) {
     name = name.toLowerCase();
     List<String> values = _headers[name];
@@ skipping 329 matching lines @@
     List<String> values = new List<String>();
     _headers[name] = values;
     values.add(value);
   }
 
   _checkMutable() {
     if (!_mutable) throw new HttpException("HTTP headers are not mutable");
   }
 
   _updateHostHeader() {
-    bool defaultPort = _port == null || _port == HttpClient.DEFAULT_HTTP_PORT;
+    bool defaultPort = _port == null || _port == _defaultPortForScheme;
     String portPart = defaultPort ? "" : ":$_port";
     _set("host", "$host$portPart");
   }
 
   _foldHeader(String name) {
     if (name == HttpHeaders.SET_COOKIE ||
         (_noFoldingHeaders != null &&
          _noFoldingHeaders.indexOf(name) != -1)) {
       return false;
     }
@@ skipping 506 matching lines @@
   void clear() {
     throw new UnsupportedError("Cannot modify an unmodifiable map");
   }
   void forEach(void f(K key, V value)) => _map.forEach(f);
   Iterable<K> get keys => _map.keys;
   Iterable<V> get values => _map.values;
   int get length => _map.length;
   bool get isEmpty => _map.isEmpty;
   bool get isNotEmpty => _map.isNotEmpty;
 }