Recalculate forms after command form changes
notifyFormChanged is called by documentcommands when
Form fields are changed. E.g. by Undo / Redo.
We need to recalculate after such changes.
Tested with simple_calculate example.
Run the unit test with the added line commented out and it failed, with the added line it passes.
Subscribers: aacid, ltoscano
Maniphest Tasks: T7805
Differential Revision: https://phabricator.kde.org/D10547