Fix some warnings for Windows.

In the deprecated class Implicit_vector_to_labeled_function_wrapper,
an implicit conversion from an unsigned int to a signed int caused a warning.
On windows, pragma message needs parenthesis.

Author: aympelle

Mesh_3/include/CGAL/Mesh_3/Implicit_to_labeled_function_wrapper.h

@@ -38,7 +38,7 @@
 #ifdef __GNUG__
 #warning deprecated : use <CGAL/Labeled_mesh_domain_3.h> instead.
 #else
-#pragma message "WARNING (deprecated) : use <CGAL/Labeled_mesh_domain_3.h> instead."
+#pragma message("WARNING (deprecated) : use <CGAL/Labeled_mesh_domain_3.h> instead.")
 #endif
 
 #include <vector>
@@ -121,7 +121,7 @@ class Implicit_vector_to_labeled_function_wrapper
   /// Operator ()
   return_type operator()(const Point_3& p, const bool = true) const
   {
-    int nb_func = function_vector_.size();
+    int nb_func = static_cast<int>(function_vector_.size());
     if ( nb_func > 8 )
     {
       CGAL_error_msg("We support at most 8 functions !");

Mesh_3/include/CGAL/Mesh_3/Labeled_mesh_domain_3.h

@@ -29,7 +29,7 @@
 #ifdef __GNUG__
 #warning deprecated : use <CGAL/Labeled_mesh_domain_3.h> instead.
 #else
-#pragma message "WARNING (deprecated) : use <CGAL/Labeled_mesh_domain_3.h> instead."
+#pragma message("WARNING (deprecated) : use <CGAL/Labeled_mesh_domain_3.h> instead.")
 #endif
 
 #include <CGAL/Mesh_3/config.h>