anchor.diff:  
           if (fileContentsHash != _lastSavedHash) {
             _lastSavedHash = fileContentsHash;
  -          replaceContents(text);
  +          _replaceContents(text);
           }
         });
       }
  
positive.code: 
        _invokeReconcile();
      } finally {
        _aceSubscription = _session.onChange.listen((_) => dirty = true);
      }
    }
  
  
negative.code:     String oldValue = _session.value;
      String newValue = new CssBeautify().format(oldValue);
      if (newValue != oldValue) {
        _replaceContents(newValue);
        dirty = true;
      }
    }
  