Opening the macro editor mutates the item's flag data

[krbz999]

This is pretty minor. Steps to reproduce:

• Create item macro in an item. See in the console that it has all the data such as "author" and "_id".
• Unset a value such as "author", "ownership", or "_id". See in the console that these values are now gone.
• Open the item macro editor. Do not make any changes.
• Close the editor (this performs no update on the item).
• See in the console that the flag data for the item macro has all the values previously removed.