Fix empty zlib deflate and early close of responses.

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;
 
 class _HttpIncoming extends Stream<List<int>> {
   final int _transferLength;
   final Completer _dataCompleter = new Completer();
   Stream<List<int>> _stream;
@@ skipping 387 matching lines @@
     _writeHeaders();
     return _ioSink.consume(stream);
   }
 
   Future<T> writeStream(Stream<List<int>> stream) {
     _writeHeaders();
     return _ioSink.writeStream(stream).then((_) => this);
   }
 
   void close() {
-    if (!_headersWritten && !_ignoreBody && headers.chunkedTransferEncoding) {
+    // TODO(ajohnsen): Currently, contentLength, chunkedTransferEncoding and
+    // persistentConnection is not guaranteed to be in sync.
+    if (!_headersWritten && !_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;
     }
     _writeHeaders();
     _ioSink.close();
   }
 
   Future<T> get done {
     _writeHeaders();
     return _ioSink.done;
   }
 
   void _writeHeaders() {
     if (_headersWritten) return;
     _headersWritten = true;
     _ioSink.encoding = Encoding.ASCII;
     headers._synchronize();  // Be sure the 'chunked' option is updated.
     bool asGZip = false;
     bool isServerSide = this is _HttpResponse;
     if (isServerSide && headers.chunkedTransferEncoding) {
       var response = this;
       List acceptEncodings =
           response._httpRequest.headers[HttpHeaders.ACCEPT_ENCODING];
       List contentEncoding = headers[HttpHeaders.CONTENT_ENCODING];
       if (acceptEncodings != null &&
-          acceptEncodings.any((encoding) => encoding.toLowerCase() == "gzip") &&
+          acceptEncodings
+              .expand((list) => list.split(","))
+              .any((encoding) => encoding.trim().toLowerCase() == "gzip") &&
           contentEncoding == null) {
         headers.set(HttpHeaders.CONTENT_ENCODING, "gzip");
         asGZip = true;
       }
     }
     _writeHeader();
     _ioSink = new IOSink(new _HttpOutboundConsumer(_ioSink, _consume, asGZip));
     _ioSink.encoding = encoding;
   }
 
@@ skipping 351 matching lines @@
 
 // Transformer that transforms data to HTTP Chunked Encoding.
 class _ChunkedTransformer extends StreamEventTransformer<List<int>, List<int>> {
   void handleData(List<int> data, EventSink<List<int>> sink) {
     sink.add(_chunkHeader(data.length));
     if (data.length > 0) sink.add(data);
     sink.add(_chunkFooter);
   }
 
   void handleDone(EventSink<List<int>> sink) {
-    handleData([], sink);
+    handleData(const [], sink);
     sink.close();
   }
 
   static List<int> _chunkHeader(int length) {
     const hexDigits = const [0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
                              0x38, 0x39, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46];
     var header = [];
     if (length == 0) {
       header.add(hexDigits[length]);
     } else {
@@ skipping 891 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;
 }