status files: trying out new SkipSlow flag

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.
 
 package/invalid_uri_test: Fail, OK # CompileTimeErrors intentionally
@@ skipping 108 matching lines @@
 javascript_int_overflow_test: Skip # --throw_on_javascript_int_overflow not supported on MIPS.
 
 [ $arch == mips ]
 io/signals_test: Fail # Issue 17440
 io/file_stat_test: Fail # Issue 17440
 io/process_sync_test: Skip # Starts 10 dart subprocesses, uses too much memory.
 io/signals_test: Skip # Starts 10 dart subprocesses, uses too much memory
 io/file_read_special_device_test: Fail # Issue 17440
 
 [ $arch == mips && $mode == debug ]
-io/web_socket_test: Skip # Times out. Issue 20352
+io/web_socket_test: SkipSlow # Times out. Issue 20352
 io/test_runner_test: Skip # Flakily times out in a subtest. Issue 201351
-full_coverage_test: Skip # Times out. Issue 20352
+full_coverage_test: SkipSlow # Times out. Issue 20352
 io/http_client_stays_alive_test: Skip # Timing dependent test, MIPS machine too slow.
 
 [ $compiler == none && ($runtime == dartium || $runtime == ContentShellOnAndroid) && $unchecked ]
 assert_test: Fail # Issue 13719: Please triage this failure.
 
 [ $compiler == none && ($runtime == dartium || $runtime == ContentShellOnAndroid) ]
 javascript_int_overflow_literal_test/01: Fail # Issue 13719: Please triage this failure.
 javascript_int_overflow_test: Fail # Issue 13719: Please triage this failure.
 
 [ $compiler == dartanalyzer || $compiler == dart2analyzer ]
@@ skipping 17 matching lines @@
 io/skipping_dart2js_compilations_test: Fail # Issue 19551.
 
 [ $arch != ia32 && $arch != x64 && $arch != simarm && $mode == debug ]
 verified_mem_test: Skip  # Not yet implemented.
 
 [ $runtime == vm && $mode == debug && $builder_tag == asan ]
 full_coverage_test: Skip  # Timeout.
 io/file_lock_test: Skip  # Timeout.
 io/test_runner_test: Skip  # Timeout.
 io/http_client_stays_alive_test: Skip  # Timeout.