Don't close stdio/stderr when shutting down.

tests/standalone/standalone.status

 # 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.
 
 # WARNING:
 # Tests using the multitest feature where failure is expected should *also* be
 # listed in tests/lib/analyzer/analyze_tests.status without the "standalone"
 # prefix.
 
 packages_file_test: Skip # Issue 26715
@@ skipping 234 matching lines @@
 io/skipping_dart2js_compilations_test: Skip # Platform.executable
 io/snapshot_fail_test: Skip # Platform.executable
 io/stdin_sync_test: Skip # Platform.executable
 io/test_extension_fail_test: Skip # Platform.executable
 io/file_read_special_device_test: Skip # Platform.executable
 verbose_gc_to_bmu_test: Skip # Platform.executable
 io/http_server_close_response_after_error_test: Skip # Platform.executable
 io/http_client_stays_alive_test: Skip # Platform.executable
 io/print_sync_test: Skip # Platform.executable
 io/signals_test: Skip # Platform.executable
+io/stdio_implicit_close_test: Skip # Platform.executable
 io/stdio_nonblocking_test: Skip # Platform.executable
 io/regress_7191_test: Skip # Platform.executable
 io/secure_unauthorized_test: Skip # Platform.executable
 io/dart_std_io_pipe_test: Skip # Platform.executable
 io/platform_test: Skip # Platform.executable
 io/socket_cross_process_test: Skip # Platform.executable
 io/test_runner_test: Skip # Platform.executable
 io/file_lock_test: Skip # Platform.executable
 io/code_collection_test: Skip # Platform.executable
 io/file_blocking_lock_test: Skip # Platform.executable
@@ skipping 15 matching lines @@
 
 # Overriding these flags are not supported in product mode.
 [ $mode == product ]
 no_profiler_test: SkipByDesign
 no_support_coverage_test: SkipByDesign
 no_support_debugger_test: SkipByDesign
 no_support_disassembler_test: SkipByDesign
 no_support_il_printer_test: SkipByDesign
 no_support_service_test: SkipByDesign
 no_support_timeline_test: SkipByDesign
+io/stdio_implicit_close_test: Skip # SkipByDesign
 
 # Following tests are skipped on dart_app as package mapping is not supported.
 [ $runtime == dart_precompiled || $runtime == dart_app ]
 package/scenarios/packages_file_strange_formatting/mixed_line_ends_test: Skip
 package/scenarios/packages_file_strange_formatting/empty_lines_test: Skip
 package/scenarios/invalid/invalid_utf8_test: Skip
 package/scenarios/invalid/same_package_twice_test: Skip
 package/scenarios/invalid/non_existent_packages_file_test: Skip
 package/scenarios/empty_packages_file/empty_packages_file_noimports_test: Skip
 package/scenarios/packages_option_only/packages_option_only_noimports_test: Skip
@@ skipping 27 matching lines @@
 package/*: SkipByDesign # Launches VMs in interesting ways.
 
 [ $builder_tag == no_ipv6 ]
 io/http_bind_test: Skip
 io/raw_datagram_socket_test: Skip
 io/socket_source_address_test: Skip
 io/socket_bind_test: Skip
 io/http_proxy_advanced_test: Skip
 io/http_ipv6_test: Skip
 io/socket_ipv6_test: Skip