- erroneous double logic for subset meshes.
The underlying vtk::vtuCells uses a cellMap to map into a global
field, which also allows handling of decomposed polyhedral cells.
If a mesh subset is involved (eg, cellSet, cellZone), then the
set/zone cellMap can be used to ensure that the original number is
properly adjusted. For foamToVTK, the meshSubsetHelper already
does the subsetting and is used when loading fields.
Does not affect ParaView reader module since there we work on the
full field and do the subsetting manually (using the cellMap).