Mark this as deprecated.

The calendar parameter was never implemeneted correctly. The API method
doesn't take a calendar parameter, and the parameter that is *expected*
to be passed here is the $range parameter. Can't remove the method
parameter for BC reasons, but at least don't pass the incorrect value
for $range.

framework/Core/lib/Horde/Core/ActiveSync/Connector.php

@@ -211,11 +211,11 @@ public function calendar_replace($uid, Horde_ActiveSync_Message_Appointment $con
      * Delete an event from Horde's calendar storage
      *
      * @param string $uid  The UID of the event to delete
-     * @param string $calendar  The calendar id. @since 2.12.0
+     * @param string $calendar  The calendar id. @since 2.12.0 @deprecated (unused).
      */
     public function calendar_delete($uid, $calendar = null)
     {
-        $this->_registry->calendar->delete($uid, null, $calendar);
+        $this->_registry->calendar->delete($uid);
     }
 
     /**