I found out that way that <CGAL/Mesh_3/Refine_facets.h> and
<CGAL/Mesh_3/Protect_edges_sizing_field> were using global functions
instead of functors of the traits class.
Note also the funny bug that <CGAL/Regular_triangulation_cell_base_3.h> was
depending on <CGAL/Triangulation_vertex_base_3.h>!