Delete in empty cell advances cell in TableRow.nodes collection

[cameracker]

This is kind of hard to describe so here's a gif :)

http://recordit.co/ua7AwFMWey

Steps to reproduce

1. Add text in a cell in a row (first cell of the row is a good choice).
2. Select an empty cell after it in the same row
3. Hit delete.

Root cause is the way cells are readded when the rows have same amount of cells validation rule fires.