std::result of is deprecated in C++17 (#3244)
std::result of is deprecated in C++17 (#3244)

dschwen/libmesh,jwpeterson/libmesh,jwpeterson/libmesh,dschwen/libmesh,dschwen/libmesh,libMesh/libmesh,dschwen/libmesh,jwpeterson/libmesh,libMesh/libmesh,libMesh/libmesh,libMesh/libmesh,libMesh/libmesh,jwpeterson/libmesh,dschwen/libmesh,jwpeterson/libmesh,libMesh/libmesh,libMesh/libmesh,dschwen/libmesh,jwpeterson/libmesh,jwpeterson/libmesh,dschwen/libmesh,libMesh/libmesh,dschwen/libmesh,jwpeterson/libmesh