GUACAMOLE-2005: FIlter out batches that ended up not having any keystroke events.

guacamole/src/main/frontend/src/app/player/services/keyEventDisplayService.js

@@ -361,8 +361,8 @@ angular.module('player').factory('keyEventDisplayService',
 
         });
 
-        // All processed batches
-        return batches;
+        // All processed batches with events
+        return batches.filter(batch => batch.events.length > 0);
 
     };