Process facestream in vtkExtractUnstructuredGridPiece::RequestData.

Change-Id: Ib8b168a0c443fe945d78bb16bf1159cff14abdd7
Handle polyhedra in vtkUnstructuredGridWriter.

Change-Id: I6c20eb8650e2b079c8b1f581c9727a3d8205087a
Merge topic '14258-remote-polyhedra' into master

c8bec1f2 Handle polyhedra in vtkUnstructuredGridWriter.
42b0733e Process facestream in vtkExtractUnstructuredGridPiece::RequestData.