Merge branch 'hotfix/3.1.3' into develop

Conflicts:
	system/docs/CHANGELOG.md

src/Resources/contao/dca/tl_calendar_events.php

@@ -904,18 +904,19 @@ public function generateFeed()
 	 * modified (edit/editAll), moved (cut/cutAll) or deleted (delete/deleteAll).
 	 * Since duplicated events are unpublished by default, it is not necessary
 	 * to schedule updates on copyAll as well.
+	 * @param \DataContainer
 	 */
-	public function scheduleUpdate()
+	public function scheduleUpdate(DataContainer $dc)
 	{
 		// Return if there is no ID
-		if (!CURRENT_ID || Input::get('act') == 'copy')
+		if (!$dc->activeRecord || !$dc->activeRecord->pid || Input::get('act') == 'copy')
 		{
 			return;
 		}
 
 		// Store the ID in the session
 		$session = $this->Session->get('calendar_feed_updater');
-		$session[] = CURRENT_ID;
+		$session[] = $dc->activeRecord->pid;
 		$this->Session->set('calendar_feed_updater', array_unique($session));
 	}