Strange Behaviour in AgGrid with Tree Structure in autoGroupColumnDef

Question

I Have a TreeView in AgGrid with, my autoGroupColumnDef is a editable field, the architecture is like : https://embed.plnkr.co/VLDTtiLtkWM71qA0k43U/ the point is here:

this.autoGroupColumnDef = {
      headerName: "Files",
      editable: true,
      width: 250,
      cellRendererParams: {
        checkbox: true,
        suppressCount: true,
        innerRenderer: "fileCellRenderer"
      }
    };

When I edit and press enter it not saves the edit, therefore we must provide a valueGetter/Setter. The valueSetter is where it breaks I must remove the item from the grid and insert it again, update doesn't apply.

Is there any solution for that ? I mean editing a root autoGroupColumnDef cell, and it should also apply to all children. Its a very common use case. Provide AgGrid therefore a plunker ?