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

tests/standalone/io/zlib_test.dart

Index: tests/standalone/io/zlib_test.dart
diff --git a/tests/standalone/io/zlib_test.dart b/tests/standalone/io/zlib_test.dart
index ac9f797305358547be4def235df40870cd16b49b..a2e30d20230a2ab399638d538c500b5428d2a706 100644
--- a/tests/standalone/io/zlib_test.dart
+++ b/tests/standalone/io/zlib_test.dart
@@ -32,8 +32,7 @@ void testZLibDeflateEmptyGzip() {
         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();
@@ -49,6 +48,7 @@ void testZLibDeflate() {
         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],