This is a feature request that NVDA report selected cell coordinates.
Steps to reproduce:

1. Open Calc.
2. Press shift+downArrow.
   NVDA report: nothing
   expected: a1 through a2 selected
3. press ctrl+home to move to top.
4. Press shift+space to select entire row
   NVDA report: space
   expected: a1 through amj1 selected