Fix loss of new items in multi-valued fieds after restoring a draft

Please use the jars in the first comment to reproduce with the following scenario:

1. Navigate to a Workspace
2. Click the New button and choose Fiche d'indexation
3. Set the title to Fiche 10
4. Add 1 Auteur and fill every suggestion field with the first suggestion
5. Create the document
6. Click on the Edit tab
7. Click the Add button for Auteur and fill every suggestion field with the second suggestion
8. Set a description => the system shows a draft is saved
9. Leave the Edit form by using the refresh button of the browser: a draft is created and an alert is displayed: Refresh anyway
10. In the top right corner, the system indicates that a draft was saved: use it
11. The description is automatically filled with the old value

=> Observe that there is only 1 Auteur : the second Auteur has not been restored

The bug was reproduced against 7.10 and 9.10. It was tested against HF38 to see if NXP-24266 and the bug was already there. So it is not a regression.