code: private void requestPermissions(Activity activity, int requestCode) {
          String[] permissions = getRequiredAndroidPermissions();
          handler.requestPermissions(activity, permissions, requestCode);
      }
docs: Starts the async Permission Request. The caller activity will be notified of the result on the
  onRequestPermissionsResult method, from the ActivityCompat.OnRequestPermissionsResultCallback
  interface.
  
  @param activity    a valid activity context. It will receive the permissions
  request result on the onRequestPermissionsResult method.
  @param requestCode the code to use for the Permissions Request.