bug#21684: 25.0.50; undo in query-replace w/o exit

[Tino Calancha]

> Maybe better would be for undo "U" to only undo and skip non-replacement
> entries in the stack?  (Implementation-wise this means looping until
> finding a previous non-replacement entry in the stack).
I agree, its better undo 'just' undo. Fixed in the new patch
(replace-3.patch).

> A minor comment is that to save cons cells you could just put both new
> elements shallow as elements 3 and 4 in the stack instead of adding
> a list of them.
Sure, thank you for remind me this. Applied.

> Another minor suggestions is for better names you could rename
> the prefix -solved-regexp to -replaced
Done. Thank you.

> Also we need this feature to be documented in etc/NEWS.
> Have you already signed FSF copyright assignment papers?
I didn't. I would like to sign. Maybe someone could guide me how to
complete such process.

replace-3.patch
Description: Text document