blockMesh does not work for wedge meshes

Summary

Cells at axis of wedge meshes are hexahedra after running blockMesh. They should be prisms. This makes e.g. curl(volVectorField) break. I.e. blockMesh does not understand that if a side of a block is collapsed, the faces of that side should also be collapsed, so that the cells will be prisms. This has worked correctly in all other versions.

Steps to reproduce

Run blockMesh and then checkMesh on tutorial pimpleFoam/laminar/movingCone. There should be a number of prism cells.

Example case

Tutorial pimpleFoam/laminar/movingCone

What is the current bug behaviour?

See above

What is the expected correct behavior?

See above

Relevant logs and/or images

Present log from checkMesh:

Overall number of cells of each type:
    hexahedra:     1900
    prisms:        0
***Total number of faces on empty patches is not divisible by the number of cells in the mesh. Hence this mesh is not 1D or 2D.
***Zero or negative face area detected.  Minimum area: 0
***Max skewness = 1.22226e+146, 35 highly skew faces detected which may impair the quality of the results
  <<Writing 35 skew faces to set skewFaces

Correct log from checkMesh:

Overall number of cells of each type:
    hexahedra:     1865
    prisms:        35

Environment information

OpenFOAM version : v2006 Operating system : ubuntu Hardware info : Compiler : gcc (default)

git rev-parse --short HEAD: 6461eec8

Possible fixes

The movingCone tutorial works only because the empty condition is set on the 35 faces with zero area, but that is not how it should be done. There should not be any faces on that patch.