Add error message if facet normal is used in cell integrals

[Martin Sandve Alnæs]

From Johan Hake:

The following three lines give incomprehensible compilation error:

from dolfin import *
mesh = UnitSquare(2,2)
assemble(dot(mesh.ufl_cell().n,mesh.ufl_cell().n)*dx)

Similar checks can be implemented for all integration domain specific types.

[Martin Sandve Alnæs]

I'll fix this for 1.4.

[Martin Sandve Alnæs]

Fixed in b68b890dc1e1b1c868b4bc1a1fa44e4e16e8bde7 more generally by adding error message for any facet-geometry quantity used in any non-facet integral.

[Martin Sandve Alnæs]

Removing milestone: 1.4 (automated comment)