Loading domains from a mesh file fails when run in parallel

Loading a mesh file that also contains domain data fails to correctly load the domain data when running with MPI. The following test script creates and reloads both the mesh and the meshfunction perfectly when running it without MPI. However, when loading the mesh domains in parallel, it fails (Note, that mesh.domains().num_marked() shows that in fact not all cells are marked in parallel, hence the error occurs during loading, not when converting it into a MeshFunction).

Loading a MeshFunction directly from a file works in parallel as expected.

import os
from dolfin import *

meshfile = 'mesh.xml.gz'
subfile = 'sub.xml.gz'

if not (os.path.exists(meshfile) and
        os.path.exists(subfile)):
    mesh = UnitSquareMesh(10, 10)

    AutoSubDomain(lambda _: True).mark_cells(mesh, 1)
    AutoSubDomain(lambda x: x[0] >= 0.5).mark_cells(mesh, 2)

    subdomains = MeshFunction('size_t', mesh, 2, mesh.domains())
    File(meshfile) << mesh
    File(subfile) << subdomains

mesh = Mesh(meshfile)
sub_from_mesh = MeshFunction('size_t', mesh, 2, mesh.domains())
sub_from_file = MeshFunction('size_t', mesh, subfile)
plot(sub_from_mesh)
plot(sub_from_file)
interactive()

The bug occurs both 1.4, as well as in the master branch.

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