SetValue for whole form with shouldDirty: true

[ondrejgronych]

We save user form in progress when he wants to leave a page. When he comes back I need to set all form values back to his last state. The form is really huge and has so many fields. I need to check which of them are dirty. Now I call reset(oldFormValues), but there is no possibility to trigger check which fields are dirty. And setValue with option shouldDirty I cannot use because of the count of fields in form.