vtkCompleteArrays/vtkXMLPRectilinearGridWriter doesn't work for rectilinear grids without data on process 0
vtkCompleteArrays needs to pass the X, Y and Z arrays to process 0 if process 0 has no data on it so that the vtkXMLPRectilinearGridWriter will write out the meta-data on process 0 properly. Steps to reproduce are:
- Run ParaView and connect to a pvserver with 8 MPI processes
- Open cth.vtr which is available under ./ExternalData/Testing/Data/cth.vtr or ./ExternalData/VTK/Testing/Data/cth.vtr
- Create an Aggregate Dataset filter with Number Of Target Processes set to 3
- Save the output This will fail when trying to load the saved file back into ParaView with the message "Could not find PCoordinates element with 3 arrays".