Migrating another batch of tests to dart 2.

tests/language/closure_variable_shadow_test.dart

Index: tests/language/closure_variable_shadow_test.dart
diff --git a/tests/language/closure_variable_shadow_test.dart b/tests/language/closure_variable_shadow_test.dart
deleted file mode 100644
index 4b1edb477b4e4fb26f72850ce43bbcb30362fbfe..0000000000000000000000000000000000000000
--- a/tests/language/closure_variable_shadow_test.dart
+++ /dev/null
@@ -1,21 +0,0 @@
-// Copyright (c) 2014, 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";
-
-// The intermediate variable 'y' must either be preserved
-// or parameters must be renamed.
-
-foo(x) {
-  var y = x;
-  bar(x) {
-    return y - x;
-  }
-
-  return bar;
-}
-
-main() {
-  Expect.equals(-10, foo(10)(20));
-}