Revert "Refactor the admin maintenance screen so that events are used to

populate the action buttons and other content such as the list of scheduled
tasks."

Leaving this api out of RC1.

This reverts commit 19fee6b5e4.

Conflicts:

	modules/gallery/views/admin_maintenance.html.php

modules/gallery/views/admin_maintenance.html.php

@@ -29,21 +29,23 @@
             <?= $task->description ?>
           </td>
           <td>
-            <? foreach ($task_buttons as $button): ?>
-            <a href="<?= "{$button->url}/$task->callback?csrf=$csrf" ?>"
+            <a href="<?= url::site("admin/maintenance/start/$task->callback?csrf=$csrf") ?>"
               class="g-dialog-link g-button ui-icon-left ui-state-default ui-corner-all">
-              <?= html::clean($button->text) ?>
+              <?= t("run") ?>
             </a>
-            <? endforeach ?>
+            <? if (module::is_active("scheduler")): ?>
+            <a href="<?= url::site("form/add/admin/schedule/$task->callback?csrf=$csrf") ?>"
+              class="g-dialog-link g-button ui-icon-left ui-state-default ui-corner-all">
+              <?= t("schedule") ?>
+            </a>
+            <? endif ?>
           </td>
         </tr>
         <? endforeach ?>
       </table>
     </div>
 
-    <? foreach ($task_maintenance_content as $content): ?>
-    <?= html::purify($content) ?>
-    <? endforeach ?>
+    <?= $schedule_definitions ?>
 
     <? if ($running_tasks->count()): ?>
     <div id="g-running-tasks">