Do not set twice the result of an on_change call in a x2many

Closes #13971
(grafted from e38f22986aac2e37fa5b2ca448152f49698475e6)

--HG--
branch : 6.0

sao/src/model.js

@@ -2424,7 +2424,11 @@
                         }
                         var record2 = group.get(vals.id);
                         if (record2) {
-                            record2.set_on_change(vals);
+                            let to_update = Object.fromEntries(
+                                Object.entries(vals).filter(
+                                    ([k, v]) => !Object.prototype.hasOwnProperty.call(vals_to_set, k)
+                                ));
+                            record2.set_on_change(to_update);
                         }
                     });
                 }

tryton/tryton/gui/window/view_form/model/field.py

@@ -825,7 +825,10 @@ class O2MField(Field):
                     continue
                 record2 = group.get(vals['id'])
                 if record2 is not None:
-                    record2.set_on_change(vals)
+                    to_set = {
+                        k: v for k, v in vals.items
+                        if k not in vals_to_set}
+                    record2.set_on_change(to_set)
 
     def validation_domains(self, record, pre_validate=None):
         screen_domain, attr_domain = self.domains_get(record, pre_validate)