Add option to HttpClient to turn of auto uncompression

tests/standalone/io/http_compression_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.
 //
 // VMOptions=
 // VMOptions=--short_socket_read
 // VMOptions=--short_socket_write
 // VMOptions=--short_socket_read --short_socket_write
 
 import 'package:expect/expect.dart';
 import 'dart:io';
 import 'dart:typed_data';
 
-void testServerCompress() {
+void testServerCompress({bool clientAutoUncompress: true}) {
   void test(List<int> data) {
     HttpServer.bind("127.0.0.1", 0).then((server) {
       server.listen((request) {
         request.response.add(data);
         request.response.close();
       });
       var client = new HttpClient();
+      client.autoUncompress = clientAutoUncompress;
       client.get("127.0.0.1", server.port, "/")
           .then((request) {
             request.headers.set(HttpHeaders.ACCEPT_ENCODING, "gzip,deflate");
             return request.close();
           })
           .then((response) {
             Expect.equals("gzip",
                           response.headers.value(HttpHeaders.CONTENT_ENCODING));
             response
                 .fold([], (list, b) {
                   list.addAll(b);
                   return list;
                 }).then((list) {
-                  Expect.listEquals(data, list);
+                  if (clientAutoUncompress) {
+                    Expect.listEquals(data, list);
+                  } else {
+                    Expect.listEquals(data, GZIP.decode(list));
+                  }
                   server.close();
                   client.close();
                 });
           });
     });
   }
   test("My raw server provided data".codeUnits);
   var longBuffer = new Uint8List(1024 * 1024);
   for (int i = 0; i < longBuffer.length; i++) {
     longBuffer[i] = i & 0xFF;
@@ skipping 36 matching lines @@
   test('deflate, gzip', true);
   test('deflate ,gzip', true);
   test('deflate  ,  gzip', true);
   test('abc,deflate  ,  gzip,def,,,ghi  ,jkl', true);
   test('xgzip', false);
   test('gzipx;', false);
 }
 
 void main() {
   testServerCompress();
+  testServerCompress(clientAutoUncompress: false);
   testAcceptEncodingHeader();
 }