bug#51883: 29.0.50; Command to get accidentally deleted frames back

[Juri Linkov]

>> +    (bindings--define-key menu [undelete-last-deleted-frame]
>> +      '(menu-item "Undelete Frame" undelete-frame
>> +                  :enable undelete-frame-mode
>> +                  :help "Undelete last deleted frame"))
>
> How about using "restore" instead of "undelete", here and everywhere
> else?  I think it's a tad more clear, and also easier to understand,
> as it doesn't use negative tense.

Michael pointed out that "restore" is a too confusing name
where "restore" is opposite to making a frame fullscreen.
OTOH, "undelete" is similar to "undo", so "undelete" better explains
what it does.  And the main advantage of the name "undelete-frame"
is that it's immediately clear that it's opposite to "delete-frame".