That assertion verifies that the value `value_outside` is considered at
a value *outside* of the domain. Otherwise Mesh_3 will crash with an
assertion saying that "infinite cells should not be in the C3t3".
That is an attempt to fix a warning:
```
../include/CGAL/utility.h:101:33: warning: 'index2' may be used uninitialized in this function [-Wmaybe-uninitialized]
: first(a), second(b), third(c)
^
In file included from ../include/CGAL/Mesh_3/Mesher_3.h:35:0,
from ../include/CGAL/refine_mesh_3.h:32,
from ../include/CGAL/make_mesh_3.h:30,
from ../test/Mesh_3/test_c3t3_extract_subdomains_boundaries.cpp:9:
../include/CGAL/Mesh_3/Refine_facets_manifold_base.h:162:17: note: 'index2' was declared here
int index1, index2;
^
```
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(227): warning C4267: 'initializing': conversion from 'size_t' to 'const int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(227): warning C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(503): warning C4267: 'initializing': conversion from 'size_t' to 'const int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(503): warning C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(517): warning C4267: 'initializing': conversion from 'size_t' to 'const int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(517): warning C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(518): warning C4267: 'return': conversion from 'size_t' to 'int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(561): warning C4267: 'initializing': conversion from 'size_t' to 'const int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(561): warning C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(814): warning C4267: 'initializing': conversion from 'size_t' to 'const int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(814): warning C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(815): warning C4267: 'initializing': conversion from 'size_t' to 'const int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(815): warning C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(855): warning C4267: 'initializing': conversion from 'size_t' to 'const int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(855): warning C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(857): warning C4267: 'initializing': conversion from 'size_t' to 'const int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(857): warning C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data
> /Mesh_3/include/CGAL/Mesh_3/Refine_facets_3.h:632:25: error: declaration of 'Tr' shadows template parameter
> template<class Tr, class Cr, class MD, class C3T3_, class Ct, class C_>
For the moment, the manifold feature is no longer working.
Merge remote-tracking branch 'cgal-dev/Mesh_3-manifold_criterion-lrineau' into Mesh_3-manifold_criterion-lrineau
Conflicts:
Mesh_3/include/CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h
Mesh_3/include/CGAL/Mesh_3/Mesher_3.h
Mesh_3/include/CGAL/Mesh_3/Refine_facets_3.h
Polyhedron/demo/Polyhedron/Polyhedron_3.cpp
Polyhedron/demo/Polyhedron/Polyhedron_demo_mesh_3_plugin.cpp
Polyhedron/demo/Polyhedron/Polyhedron_demo_mesh_3_plugin_cgal_code.cpp