Use the proper syntax for logging.

xmlsitemap_custom/src/Form/XmlSitemapCustomDeleteForm.php

@@ -93,9 +93,8 @@ class XmlSitemapCustomDeleteForm extends ConfirmFormBase {
    */
   public function submitForm(array &$form, FormStateInterface $form_state) {
     $this->linkStorage->delete('custom', $this->custom_link['id']);
-    $message = $this->t('The custom link for %loc has been deleted.', array('%loc' => $this->custom_link['loc']));
-    $this->logger('xmlsitemap')->debug($message);
-    drupal_set_message($message);
+    $this->logger('xmlsitemap')->debug('The custom link for %loc has been deleted.', array('%loc' => $this->custom_link['loc']));
+    drupal_set_message($this->t('The custom link for %loc has been deleted.', array('%loc' => $this->custom_link['loc'])));
 
     $form_state->setRedirectUrl($this->getCancelUrl());
   }