Django Admin Inlines, for users who only have "view" permission on the inline model, return Validation errors.

[Matija Kolarić]

The way to reproduce:

1. Make three models, two with a FKs to the first one, and create ModelAdmin for one, that includes inlines for the other two.

2. Create a new object with both inline types with a user who has ass/change permissions to everything.

3. Open the same changeview with a user that has change permission for the main model and one of the inlines, and only view permission for the other inline model.

4. Save

What happens is that Validation Error is raised (which is not visible, but present in form.errors) stating that the fields in the inline are required.

What should happen is that the whole inline should really be ignored, basically, the behaviour should be the same as if the user did not even have the "view" permission for the inline.

[Tim Graham]

Duplicate of #29930.

[Matija Kolarić]

Also, likely related to this, if the view has save_as, and there is an error, then, although the user has only view permission for the inline mode, the formset is shown as if the user had add permission, though nothing happens with the entered data.