Make dart:io unit-tests pass the analyzer.

tests/standalone/io/http_cookie_date_test.dart

Index: tests/standalone/io/http_cookie_date_test.dart
diff --git a/tests/standalone/io/http_cookie_date_test.dart b/tests/standalone/io/http_cookie_date_test.dart
index 56bee7a9ee00a6427b6aa1d5719a5c7ea7e3cef5..08288b62914c11f4e63b7ceb51d989e72c0e330a 100644
--- a/tests/standalone/io/http_cookie_date_test.dart
+++ b/tests/standalone/io/http_cookie_date_test.dart
@@ -2,17 +2,38 @@
 // 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.
 
+library dart.io;
+
 import "package:expect/expect.dart";
 import "dart:async";
-import "dart:math";
 import "dart:collection";
+import "dart:convert";
+import "dart:math";
+import "dart:typed_data";
+import "dart:isolate";
 
+part "../../../sdk/lib/io/bytes_builder.dart";
 part "../../../sdk/lib/io/common.dart";
-part "../../../sdk/lib/io/io_sink.dart";
+part "../../../sdk/lib/io/crypto.dart";
+part "../../../sdk/lib/io/data_transformer.dart";
+part "../../../sdk/lib/io/directory.dart";
+part "../../../sdk/lib/io/directory_impl.dart";
+part "../../../sdk/lib/io/file.dart";
+part "../../../sdk/lib/io/file_impl.dart";
+part "../../../sdk/lib/io/file_system_entity.dart";
+part "../../../sdk/lib/io/link.dart";
 part "../../../sdk/lib/io/http.dart";
 part "../../../sdk/lib/io/http_impl.dart";
-part "../../../sdk/lib/io/http_parser.dart";
 part "../../../sdk/lib/io/http_date.dart";
+part "../../../sdk/lib/io/http_parser.dart";
+part "../../../sdk/lib/io/http_headers.dart";
+part "../../../sdk/lib/io/http_session.dart";
+part "../../../sdk/lib/io/io_service.dart";
+part "../../../sdk/lib/io/io_sink.dart";
+part "../../../sdk/lib/io/platform.dart";
+part "../../../sdk/lib/io/platform_impl.dart";
+part "../../../sdk/lib/io/secure_socket.dart";
+part "../../../sdk/lib/io/secure_server_socket.dart";
 part "../../../sdk/lib/io/socket.dart";
 
 void testParseHttpCookieDate() {