Fix bin scripts error ?

mobile.php

<?php
    // Are we using the mobile skin or not ?
    if ($this->api->output->type == 'html') {
      if ($this->isMobile() && strpos($skin, '_mobile') === false) {
        $skin = 'melanie2_larry_mobile';
        $this->rc->config->set('skin', $skin);
        $this->rc->output->set_env('skin', $skin);
        $this->rc->output->set_skin($skin);
      }
      elseif (! $this->isMobile() && strpos($skin, '_mobile') !== false) {
        $skin = str_replace('_mobile', '', $skin);
        $this->rc->config->set('skin', $skin);
        $this->rc->output->set_env('skin', $skin);
        $this->rc->output->set_skin($skin);
      }
      
      // Set env ismobile
      $this->rc->output->set_env('ismobile', $this->isMobile());
    }