Skip spurious constants in deferred computation.

tests/lib/lib.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.
 
 [ $unchecked ]
 mirrors/redirecting_factory_different_type_test: SkipByDesign # Tests type checks.
 
 [ $compiler == dart2js ]
 async/schedule_microtask6_test: RuntimeError # global error handling is not supported. Issue 5958
 
@@ skipping 276 matching lines @@
 
 developer/metrics_test: Fail # Issue 20309
 developer/metrics_num_test: Fail # Issue 20309
 profiler/metrics_test: Fail # Issue 20309
 profiler/metrics_num_test: Fail # Issue 20309
 
 [ ($compiler == dartanalyzer || $compiler == dart2analyzer) && $checked ]
 mirrors/regress_16321_test/01: MissingCompileTimeError # Issue 16391
 
 [ $compiler == dart2js && $runtime == d8 && $system == windows ]
-async/*deferred*: Skip # Issue 17458
-mirrors/*deferred*: Skip # Issue 17458
+async/*deferred*: Pass,RuntimeError # Issue 17458
+mirrors/*deferred*: Pass,RuntimeError # Issue 17458
 
 [ $compiler == dart2js && $mode == debug ]
 mirrors/native_class_test: Pass, Slow
 
 [ ($compiler == none || $compiler == precompiler || $compiler == dart2app) && $arch == mips ]
 async/timer_regress22626_test: Pass, RuntimeError # Issue 22626
 
 [ $arch == simarm || $arch == simarmv6 || $arch == simarmv5te ]
 convert/chunked_conversion_utf88_test: Skip  # Pass, Slow Issue 12644.
 convert/utf85_test: Skip  # Pass, Slow Issue 12644.
@@ skipping 51 matching lines @@
 mirrors/*: SkipByDesign
 
 [ $noopt || $compiler == precompiler ]
 convert/chunked_conversion_utf88_test: Pass, Timeout
 convert/utf85_test: Pass, Timeout
 
 [ $arch == simdbc || $arch == simdbc64 ]
 # TODO(vegorov) LoadField bytecode supports only up to 256 fields. Need a long
 # version.
 mirrors/accessor_cache_overflow_test: Skip