Don't match directly on gzip output of empty message, as it's not strictly specified.

tests/standalone/io/zlib_test.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.
 
 import 'dart:async';
 import 'dart:io';
 
 import "package:async_helper/async_helper.dart";
 import "package:expect/expect.dart";
 
@@ skipping 14 matching lines @@
 
 void testZLibDeflateEmptyGzip() {
   asyncStart();
   var controller = new StreamController(sync: true);
   controller.stream.transform(new ZLibEncoder(gzip: true, level: 6))
       .fold([], (buffer, data) {
         buffer.addAll(data);
         return buffer;
       })
       .then((data) {
-        Expect.listEquals([31, 139, 8, 0, 0, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 0,
-                          0, 0, 0], data);
+        Expect.listEquals([], new ZLibDecoder().convert(data));
         asyncEnd();
       });
   controller.close();
 }
 
 void testZLibDeflate() {
   asyncStart();
   var data = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];
   var controller = new StreamController(sync: true);
   controller.stream.transform(new ZLibEncoder(gzip: false, level: 6))
       .fold([], (buffer, data) {
         buffer.addAll(data);
         return buffer;
       })
       .then((data) {
+        Expect.isTrue(data.length > 0);

[Lasse Reichstein Nielsen, 2014/03/03 12:24:22]

Move where it belongs.

[Anders Johnsen, 2014/03/03 12:24:59]

Done.

         Expect.listEquals(
             [120, 156, 99, 96, 100, 98, 102, 97, 101, 99, 231, 224, 4, 0, 0,
             175, 0, 46],
             data);
         asyncEnd();
       });
   controller.add(data);
   controller.close();
 }
 
@@ skipping 167 matching lines @@
   testZLibDeflateInvalidLevel();
   testZLibInflate();
   testZLibInflateSync();
   testZlibInflateThrowsWithSmallerWindow();
   testZlibInflateWithLargerWindow();
   testZLibDeflateRaw();
   testZLibInflateRaw();
   testZlibWithDictionary();
   asyncEnd();
 }