Migrating a block of dart 1 tests to dart 2

tests/language_strong/closure6_test.dart

Index: tests/language_strong/closure6_test.dart
diff --git a/tests/language_strong/closure6_test.dart b/tests/language_strong/closure6_test.dart
deleted file mode 100644
index ea37454542a87e325d6b3a6c61722fc56b033aab..0000000000000000000000000000000000000000
--- a/tests/language_strong/closure6_test.dart
+++ /dev/null
@@ -1,23 +0,0 @@
-// Copyright (c) 2012, 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 "package:expect/expect.dart";
-
-// Test that captured final variables are correctly mangled.
-
-class A {
-  foo() {
-    length() => 400;
-    final box_0 = 28;
-    var x = 29;
-    var f = () => length() + box_0 + x + bar();
-    return f();
-  }
-
-  bar() => 42;
-}
-
-main() {
-  Expect.equals(499, new A().foo());
-}