Remove recently added --checked flag from named_pipe_script_test to make it compatible with product…

tests/standalone/io/named_pipe_script_test.dart

Index: tests/standalone/io/named_pipe_script_test.dart
diff --git a/tests/standalone/io/named_pipe_script_test.dart b/tests/standalone/io/named_pipe_script_test.dart
index 70599ed8a713fd8fbd9bb0a2e54ff8638cf9e176..ed5a659c9f50a780d5b73fe617f4406f89bb3fa8 100644
--- a/tests/standalone/io/named_pipe_script_test.dart
+++ b/tests/standalone/io/named_pipe_script_test.dart
@@ -31,7 +31,7 @@ main() async {
 
   StringBuffer output = new StringBuffer();
   Process process =
-      await Process.start(Platform.executable, ['--checked', stdinPipePath]);
+      await Process.start(Platform.executable, [stdinPipePath]);
   bool stdinWriteFailed = false;
   process.stdout.transform(UTF8.decoder).listen(output.write);
   process.stderr.transform(UTF8.decoder).listen((data) {