Use default value from base model before of inherit model for xml import

trytond/tools/convert.py

@@ -683,13 +683,13 @@ class TrytondXmlHandler(sax.handler.ContentHandler):
 
                 # we cannot update a field if it was changed by a user...
                 if key not in old_values:
-                    if key in object_ref._inherit_fields:
-                        parent_obj = self.pool.get(
-                            object_ref._inherit_fields[key][0])
-                        expected_value = parent_obj._defaults.get(
+                    if key in object_ref._columns:
+                        expected_value = object_ref._defaults.get(
                             key, lambda *a: None)(cursor, user)
                     else:
-                        expected_value = object_ref._defaults.get(
+                        inherit_obj = self.pool.get(
+                            object_ref._inherit_fields[key][0])
+                        expected_value = inherit_obj._defaults.get(
                             key, lambda *a: None)(cursor, user)
                 else:
                     expected_value = old_values[key]