Gardening: mark language/regress_28255_test SkipByDesign in configurations without mirrors.

tests/language/language.status

 # 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.
 
 # This directory contains tests that are intended to show the
 # current state of the language.
 
 [ $compiler == none || $compiler == app_jit ]
 null_is_bottom_test/22: RuntimeError # Issue 28025
 null_is_bottom_test/34: RuntimeError # Issue 28025
@@ skipping 187 matching lines @@
 no_such_method_test: SkipByDesign
 null_test/none: SkipByDesign
 overridden_no_such_method_test: SkipByDesign
 redirecting_factory_reflection_test: SkipByDesign
 regress_13462_0_test: SkipByDesign
 regress_13462_1_test: SkipByDesign
 regress_18535_test: SkipByDesign
 super_call4_test: SkipByDesign
 super_getter_setter_test: SkipByDesign
 vm/reflect_core_vm_test: SkipByDesign
+regress_28255_test: SkipByDesign

[zra, 2017/01/05 18:36:10]

It looks like the kernel status file also needs an update, but I don't know
where to add an entry to it for this test.

[zra, 2017/01/05 20:29:55]

https://github.com/dart-lang/sdk/commit/cf1a432ac71dfd6c7e1ebf516a27bdeaea74ff95

 
 [ $noopt ]
 # Deferred loading happens eagerly. Issue #27587
 regress_23408_test: Fail
 deferred_inheritance_constraints_test/redirecting_constructor: Fail
 deferred_global_test: Fail
 deferred_load_constants_test/02: Fail
 deferred_load_constants_test/03: Fail
 deferred_load_constants_test/05: Fail
 regress_22443_test: Fail
@@ skipping 129 matching lines @@
 # Issue #28236
 async_await_test: StaticWarning
 async_star_pause_test: StaticWarning
 async_star_test: StaticWarning
 regress_18535_test: StaticWarning
 
 [ $runtime == dart_precompiled || $runtime == vm || $runtime == dartium]
 null_bottom_test/none: RuntimeError # Issue 28025
 null_bottom_test/01: RuntimeError # Issue 28025
 null_bottom_test/02: RuntimeError # Issue 28025