Don't pile up modifications in history log.

The changes introduced for request #10249 did accumulate all event
modifications in the history log, which eventually lead to bug #13113. Until
Horde_History doesn't scale better for large user numbers, we should not log
even more stuff. Especially if we don't even use this information anywhere.

kronolith/lib/Driver/Sql.php

@@ -632,7 +632,7 @@ protected function _updateEvent(Kronolith_Event $event)
         /* Log the modification of this item in the history log. */
         if ($event->uid) {
             try {
-                $GLOBALS['injector']->getInstance('Horde_History')->log('kronolith:' . $this->calendar . ':' . $event->uid, $history, false);
+                $GLOBALS['injector']->getInstance('Horde_History')->log('kronolith:' . $this->calendar . ':' . $event->uid, $history, true);
             } catch (Exception $e) {
                 Horde::log($e, 'ERR');
             }
@@ -643,7 +643,7 @@ protected function _updateEvent(Kronolith_Event $event)
          * change. */
         if ($event->baseid) {
             try {
-                $GLOBALS['injector']->getInstance('Horde_History')->log('kronolith:' . $this->calendar . ':' . $event->baseid, $history, false);
+                $GLOBALS['injector']->getInstance('Horde_History')->log('kronolith:' . $this->calendar . ':' . $event->baseid, $history, true);
             } catch (Exception $e) {
                 Horde::log($e, 'ERR');
             }