Blender Git Loki

Fix T45577 tiled sculpting not working with brushes requiring a sculpt
plane.

Make sure sculpt plane is recalculated for every tiled dab.

Note this is not the optimum thing to do, we could cache the original
sculpt plane and reuse that, but this would require us to rearrange the
logic of tiled sculpting somewhat. This can be a TODO, but for now this
will fix the issue.