[test.dart] Complain if there is non-utf8 formatted data in test output

tests/standalone/standalone.status

Index: tests/standalone/standalone.status
diff --git a/tests/standalone/standalone.status b/tests/standalone/standalone.status
index bbe3b40e4092892de5e6a8deccc6e850da48c264..3f38fb035b924c8793aaf9b09261822e4104a158 100644
--- a/tests/standalone/standalone.status
+++ b/tests/standalone/standalone.status
@@ -7,6 +7,10 @@
 # listed in tests/lib/analyzer/analyze_tests.status without the "standalone"
 # prefix.
 
+# This test checks that the test runner correctly detects and reports non-utf8
+# output from a test.
+io/non_utf8_output_test: NonUtf8Output, OK
+
 io/raw_socket_test: Pass, RuntimeError # Issue 28288
 io/http_close_test: Pass, RuntimeError # Issue 28380
 packages_file_test: Skip # Issue 26715
@@ -393,7 +397,9 @@ io/secure_socket_test: RuntimeError
 io/raw_secure_socket_test: RuntimeError
 io/https_bad_certificate_test: RuntimeError
 io/secure_server_closing_test: RuntimeError
-io/console_unicode_test: Skip # https://github.com/dart-lang/sdk/issues/28872
+# The Android command runner doesn't correctly handle non-UTF8 formatted output.
+# https://github.com/dart-lang/sdk/issues/28872
+io/non_utf8_output_test: Skip
 
 [ $system == android && $runtime == dart_precompiled && $mode == release && $arch == arm]
 io/stdout_stderr_non_blocking_test: Pass, Timeout # Issue 28426