Implement sumfact spatial coordinate

python/dune/perftool/sumfact/__init__.py

 from dune.perftool.sumfact.quadrature import (quadrature_inames,
                                               quadrature_weight,
+                                              pymbolic_quadrature_position_in_cell,
                                               )
 
 from dune.perftool.sumfact.basis import (lfs_inames,
@@ -38,3 +39,7 @@ class SumFactInterface(PDELabInterface):
 
     def pymbolic_quadrature_weight(self):
         return quadrature_weight()
+
+    def pymbolic_spatial_coordinate(self, restriction):
+        from dune.perftool.pdelab.geometry import to_global
+        return to_global(pymbolic_quadrature_position_in_cell(restriction))