EZP-27750: Backport of EZP-25478: Restore items whose original location has been deleted

[jacek-foremski]

JIRA issue: EZP-27750.

After deleting the parent content, the children are also put into the trash. Even after someone restores the parent, the children still cannot be restored (information "Item's ancestors are in Trash" is still showing). This can be circumvented in eZ Platform 1.10 by using the button "Restore under a new parent", but there is no such button in eZ Platform 1.7 and this means that the children cannot be restored at all using the Platform UI.

This PR is the backport of #819. It backported almost cleanly, with one conflict in the Resources/translations/trash.en.xlf file (the date).
It allows circumventing the issue EZP-27750 as the "Restore under a new parent" button would then be available for the children.

[andrerom]

@dpobel is on vacation, and since it's already been approved before if @yannickroger is ok with this I think we are good to go.

[yannickroger]

Look good. Make sure to have QA test it before merge and we are all good.

[jacek-foremski]

Sent to the QA.

[jacek-foremski]

Verified by the QA.