message: Improve interpolators map key.
diff: @@ -1584,10 +1584,9 @@ void InterpolationManager::RegisterFaceCoarseToFineInterpolation(
  const DenseMatrix* ptMat = fes.GetMesh()->GetNCFacesPtMat(face.ncface);
  // In the case of non-conforming slave shared face the master face is elem1.
  const int master_side = face.IsSharedNonConformingSlave() ? 0 : 1;
  - // const int face_key = master_side == 1 ?
  - // face.elem_1_local_face + 6*face.elem_2_local_face :
  - // face.elem_2_local_face + 6*face.elem_1_local_face ;
  - const int face_key = face_index;
  + const int face_key = (master_side == 0 ? 1000 : 0) +
  + face.elem_1_local_face + 6*face.elem_2_local_face +
  + 36*face.elem_2_orientation ;
  // Unfortunately we can't trust unicity of the ptMat to identify the transformation.
  Key key(ptMat, face_key);
  auto itr = interp_map.find(key);
  