Roofs are not selectable if above slice level

When a room is tall enough to surpass the height of a cropped above ground mine, it becomes unselectable.

Steps to reproduce:

  1. Start a mine in a wall of a hill
  2. Toggle slice mode
  3. New builder - make a new room
  4. Make a roof on top of the room
  5. Decide to try and resize the roof

Expected Results:
Roof can be manipulated.

Actual Results:
Roof knows it’s selected but there are no widgets.

Using slab tool on this roof also shows no ghost of the slab.

Version Number and Mods in use: r-848, better stockpiles