Fix for errors in unit tests
Fix for errors in unit tests

I'm not sure why any *other* code would be playing with data-less
System objects, but there's no need to retain extra code whose only
affect is to break them.

Mbewu/libmesh,Mbewu/libmesh,Mbewu/libmesh,Mbewu/libmesh,Mbewu/libmesh,Mbewu/libmesh,Mbewu/libmesh,Mbewu/libmesh,Mbewu/libmesh