Data management reset, effective, but view is not updated and becomes unresponsive

[eppfel]

Seems like regression; in Chrome and Safari. Maybe from changing the timestamps to a readable format.

Uncaught TypeError: Cannot read property 'map' of null
    at ui/assets/rose.js:5847
    at Object.a.onSuccess (invoke_async.js:3)
    at Object.v [as KangoInvokeAsyncModule_result] (invoke_async.js:3)
    at Array.<anonymous> (invoke_async.js:3)
    at Core.dispatchEvent (utils.js:3)
    at Core.fireEvent (utils.js:3)
    at MessageRouter.fireMessageEvent (messaging.js:3)
    at MessageRouter.<anonymous> (messaging.js:3)
    at utils.js:3

Safari is more verbose:

[Error] TypeError: null is not an object (evaluating 'data.map')
	(anonyme Funktion) (rose.js:6064)

Relates to backup.js:

var getItem = function getItem(key, dateKeys) {
    return new _ember['default'].RSVP.Promise(function (resolve) {
      kango.invokeAsyncCallback('localforage.getItem', key, function (data) {
        if (dateKeys) {
          data = data.map(addDateString(dateKeys));
        }
        resolve({
          type: key,
          data: data
        });
      });
    });
  };

If data is returned as null, the error occurs.