anchor.diff:    }
   
     @override
  -  bool get supportsScreenshot => screenshotPath != null && screenshotPath.isNotEmpty;
  +  bool get supportsScreenshot => _screenshotPath != null && _screenshotPath.isNotEmpty;
   
     @override
     Future<Null> takeScreenshot(File outputFile) {
  -    return runCheckedAsync(<String>[screenshotPath, outputFile.path]);
  +    return runCheckedAsync(<String>[_screenshotPath, outputFile.path]);
     }
   }
   
  
positive.code:   }
  
    String _installerPath;
    String get installerPath => _installerPath;
  
    String _iproxyPath;
    String get iproxyPath => _iproxyPath;
  
    String _loggerPath;
    String get loggerPath => _loggerPath;
  
    String _screenshotPath;
    String get screenshotPath => _screenshotPath;
  
    String _pusherPath;
    String get pusherPath => _pusherPath;
  
    @override
    bool get supportsHotMode => true;
  
negative.code:   @override
    Future<bool> uninstallApp(ApplicationPackage app) async {
      try {
        await runCheckedAsync(<String>[_installerPath, '-U', app.id]);
        return true;
      } catch (e) {
        return false;
  