Can't upload custom logo in theme

After updating Media and File Entity, I can't upload my custom logo in my purchased theme.

Here are the error

Warning: array_flip(): Can only flip STRING and INTEGER values! in DrupalDefaultEntityController->load() (line 175 of /Users/johndoe/template/includes/entity.inc).

PHP Fatal error: Call to undefined function theme951_form_system_theme_settings_submit() in /Users/johndoe/template/includes/form.inc on line 1520

line 1520: $function($form, $form_state);

  foreach ($handlers as $function) {
    // Check if a previous _submit handler has set a batch, but make sure we
    // do not react to a batch that is already being processed (for instance
    // if a batch operation performs a drupal_form_submit()).
    if ($type == 'submit' && ($batch =& batch_get()) && !isset($batch['id'])) {
      // Some previous submit handler has set a batch. To ensure correct
      // execution order, store the call in a special 'control' batch set.
      // See _batch_next_set().
      $batch['sets'][] = array('form_submit' => $function);
      $batch['has_form_submits'] = TRUE;
    }
    else {
      $function($form, $form_state);
    }
    $return = TRUE;
  }
  return $return;
}

How can I fix this?