Clean up HttpHeaders to always have them in a consistent state.

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 _HEADERS_BUFFER_SIZE = 8 * 1024;
 
 class _HttpIncoming extends Stream<List<int>> {
   final int _transferLength;
@@ skipping 77 matching lines @@
 
   final _HttpConnection _httpConnection;
 
   _HttpSession _session;
 
   _HttpRequest(_HttpResponse this.response,
                _HttpIncoming _incoming,
                _HttpServer this._httpServer,
                _HttpConnection this._httpConnection)
       : super(_incoming) {
-    response.headers.persistentConnection = headers.persistentConnection;
+    if (headers.protocolVersion == "1.1") {
+      response.headers.chunkedTransferEncoding = true;
+      response.headers.persistentConnection = headers.persistentConnection;
+    }
 
     if (_httpServer._sessionManagerInstance != null) {
       // Map to session if exists.
       var sessionIds = cookies
           .where((cookie) => cookie.name.toUpperCase() == _DART_SESSION_ID)
           .map((cookie) => cookie.value);
       for (var sessionId in sessionIds) {
         _session = _httpServer._sessionManager.getSession(sessionId);
         if (_session != null) {
           _session._markSeen();
@@ skipping 376 matching lines @@
       try {
         _writeHeader();
       } catch (error) {
         // Headers too large.
         throw new HttpException(
             "Headers size exceeded the of '$_HEADERS_BUFFER_SIZE' bytes");
       }
     }
     if (_headersWritten) return new Future.value();
     _headersWritten = true;
-    headers._synchronize();  // Be sure the 'chunked' option is updated.
     _dataSink.encoding = encoding;
     bool isServerSide = this is _HttpResponse;
     if (isServerSide) {
       var response = this;
       if (headers.chunkedTransferEncoding) {
         List acceptEncodings =
             response._httpRequest.headers[HttpHeaders.ACCEPT_ENCODING];
         List contentEncoding = headers[HttpHeaders.CONTENT_ENCODING];
         if (acceptEncodings != null &&
             acceptEncodings
@@ skipping 30 matching lines @@
             stream = stream.transform(const _ChunkedTransformer());
           } else if (contentLength >= 0) {
             stream = stream.transform(
                 new _ContentLengthValidator(contentLength, _uri));
           }
           return _headersSink.addStream(stream);
         });
   }
 
   Future _close() {
-    // TODO(ajohnsen): Currently, contentLength, chunkedTransferEncoding and
-    // persistentConnection is not guaranteed to be in sync.
     if (!_headersWritten) {
       if (!_ignoreBody && headers.contentLength == -1) {
         // If no body was written, _ignoreBody is false (it's not a HEAD
         // request) and the content-length is unspecified, set contentLength to
         // 0.
         headers.chunkedTransferEncoding = false;
         headers.contentLength = 0;
       } else if (!_ignoreBody && headers.contentLength > 0) {
         _headersSink.addError(new HttpException(
             "No content while contentLength was specified to be greater "
@@ skipping 368 matching lines @@
                      Uri uri,
                      String this.method,
                      _Proxy this._proxy,
                      _HttpClient this._httpClient,
                      _HttpClientConnection this._httpClientConnection)
       : super(uri, "1.1", outgoing),
         uri = uri {
     // GET and HEAD have 'content-length: 0' by default.
     if (method == "GET" || method == "HEAD") {
       contentLength = 0;
+    } else {
+      headers.chunkedTransferEncoding = true;
     }
   }
 
   Future<HttpClientResponse> get done {
     if (_response == null) {
       _response = Future.wait([_responseCompleter.future,
                                super.done])
         .then((list) => list[0]);
     }
     return _response;
@@ skipping 1606 matching lines @@
 
 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)';
 }