fbl_login_default_validators function called

While looking up to the code i saw unwanted code.

/**
* Callback function for user_login validator.
*/
function fbl_login_default_validators() {
return array(
'fbl_login_name_validate',
'user_login_name_validate',
'user_login_authenticate_validate',
'user_login_final_validate',
);
}

- - 58 $form['#validate'] = fbl_login_default_validators();
++ 58 array_unshift($form['#validate'], 'fbl_login_name_validate');

instead of redefining the validation array again and again. what you can do is give priority to your custom validation.
that way you don't need one more function to add your custom validator.