Arch: Fixed regression in structures

src/Mod/Arch/ArchComponent.py

@@ -615,6 +615,8 @@ class Component(ArchIFC.IfcProduct):
 
         # Get the object's normal.
         n = DraftGeomUtils.getNormal(shape[0])
+        if (not n) or (not n.Length):
+            n = FreeCAD.Vector(0, 0, 1)
 
         # Reverse the normal if the hint vector and the normal vector have more
         # than a 90 degree angle between them.

src/Mod/Arch/ArchStructure.py

@@ -739,7 +739,7 @@ class _Structure(ArchComponent.Component):
                     if obj.Base.Shape.Solids:
                         return None
                     elif obj.Base.Shape.Faces:
-                        if not DraftGeomUtils.isCoplanar(obj.Base.Shape.Faces,tolerance=0.01):
+                        if not DraftGeomUtils.isCoplanar(obj.Base.Shape.Faces,tol=0.01):
                             return None
                         else:
                             base,placement = self.rebase(obj.Base.Shape)