keyboard navigation -> click checkbox, press shift, click an underlying checkbox -> not all selected

[AlexAndBear]

@lookacat we've already spoken about that:

If I click a checkbox, press shift, and click the checkbox at the end of the list, not all items in between get selected

[kulmann]

The linked PR fixes the issue but unfortunately opens up a new one.

Steps to reproduce:

1. Have a folder with e.g. 4 files/folders
2. Click on the first one
3. Hold SHIFT and click the checkbox (!) of the last row

Expected behaviour

The range of files/folders gets selected AND since all items in the list have been selected the Select all checkbox in the table header also gets checked.

Actual behaviour

Actually two glitches:

1. The Select all checkbox in the table header doesn't get checked
2. If you deselect one of the items again via click on the checkbox, the Select all checkbox gets checked (indicating that all items are selected) although one item is now deselected.