### Bug report

When the Kendo UI Grid widget in "Popup" edit mode has more than one level of grouping, and when the adding of a new record is canceled, the group headers of the empty row are not removed.

### Reproduction of the problem

  1. Group the Grid by 2 columns;

  2. Click the "Add new record" button;

  3. Click the "Cancel" button in the Popup form;

  4. The empty row for the new record is removed, but the group header of the first group remains. 

A Dojo sample for reproduction: https://dojo.telerik.com/UgARObuZ

### Expected/desired behavior

The group headers of the empty row should be removed when the adding of a new record is canceled.


### Environment

* **Kendo UI version: 2021.2.616
* **jQuery version: 1.12.4
* **Browser:** [all]