Remove dart:platform library.

tests/lib/platform/executable_arguments_test.dart

Index: tests/lib/platform/executable_arguments_test.dart
diff --git a/tests/lib/platform/executable_arguments_test.dart b/tests/lib/platform/executable_arguments_test.dart
deleted file mode 100644
index 8fbf0327180e1173aadbb8cb9db7a2dd2b74139b..0000000000000000000000000000000000000000
--- a/tests/lib/platform/executable_arguments_test.dart
+++ /dev/null
@@ -1,11 +0,0 @@
-// 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:platform" as platform;
-
-import "package:unittest/unittest.dart";
-
-main() {
-  expect(platform.executableArguments is List<String>, true);
-}