[BUG] 0.14.1226 "No path" if you dig behind furniture

[b0rsuk]

Savegame:
https://www.sendspace.com/file/sa0vyu

If you designate rock for digging and it's behind furniture like flowerpots, no one will ever come and dig that rock. This is in contrast to other behavior like building walls behind a work table, where colonists will come and build the walls where a rock wall once was.

If you select a colonist and right click on the rock, sometimes you can get a glimpse of "no path" message.

Another common case where this occurs is when you're expanding your hydroponic room by digging under a mountain.