Cloned from https://bugzilla.redhat.com/show_bug.cgi?id=1353104
Description of problem:
When you input invalid values into 'Name' and 'Value' fields for new Domain or Operating System entity and push submit button, parameter entry just disappear without any error shown

How reproducible:
Always

Steps to Reproduce:
1. Create new Domain entity
2. Open it and go to 'Parameters' tab
3. Push '+Add Parameter' button
4. Input invalid values (longer than 256 characters) in both fields
5. Push 'Submit' button

Actual results:
Parameter entry is disappeared and no error is shown

Expected results:
Proper (just usual one) error is shown

This seems to be caused by #13164, where we use the authorized scope
in the form, which means we loose the data about params, that the user sent
when there is a validation error.