Hide Dart Mind setting

dart/site/try/src/settings.dart

 // Copyright (c) 2014, 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.
 
 library trydart.settings;
 
 import 'user_option.dart';
 
 const BooleanUserOption _alwaysRunInWorker =
     const BooleanUserOption('alwaysRunInWorker');
@@ skipping 25 matching lines @@
 const BooleanUserOption _onlyAnalyze =
     const BooleanUserOption('onlyAnalyze');
 
 bool get onlyAnalyze => _onlyAnalyze.value;
 
 void set onlyAnalyze(bool b) {
   _onlyAnalyze.value = b;
 }
 
 const BooleanUserOption _enableDartMind =
-    const BooleanUserOption('enableDartMind');
+    const BooleanUserOption('enableDartMind', isHidden: true);
 
 bool get enableDartMind => _enableDartMind.value;
 
 void set enableDartMind(bool b) {
   _enableDartMind.value = b;
 }
 
 const BooleanUserOption _compilationPaused =
     const BooleanUserOption('compilationPaused');
 
@@ skipping 53 matching lines @@
     _compilationPaused,
     incrementalCompilation,
     live,
     enableCodeCompletion,
     _codeFont,
     _theme,
     _currentSample,
     alwaysRunInIframe,
     communicateViaBlobs,
   ];