[1.1.2624] Cannot put floor under buiding with no terrainAffordanceNeeded

[LWM]

GenConstruct's CanPlaceBlueprintOver will not allow placing a terrain (e.g., wood floor) underneath a building which has no terrainAffordanceNeeded requirement (e.g., a modded marker with terrainAffordanceNeeded of null).

Instead, the player must remove the building with no terrain requirement, put down the new floor, and then replace the building with no terrain requirement, which does not make sense.

Better would be: if the new def is a TerrainDef and the old def has no requirement, skip any terrain affordance tests.

A minor bug, but annoying when it crops up!

Thanks