Add a loading indicator to the delete form by tagging some JS on at

the end which triggers .gallery_show_loading().  Not a complete fix
for #817 but it's a start and it takes care of one place where we have
a long running process.

modules/gallery/helpers/item.php

@@ -162,6 +162,8 @@ static function get_delete_form($item) {
       "quick/delete/$item->id?page_type=$page_type", "", "post", array("id" => "g-confirm-delete"));
     $group = $form->group("confirm_delete")->label(t("Confirm Deletion"));
     $group->submit("")->value(t("Delete"));
+    $form->script("")
+      ->url(url::abs_file("modules/gallery/js/item_form_delete.js"));
     return $form;
   }
 

modules/gallery/js/item_form_delete.js

@@ -0,0 +1,5 @@
+$("#g-confirm-delete").submit(
+  function() {
+    $("#g-confirm-delete input[type=submit]").gallery_show_loading();
+  }
+);