query-replace backward

query-replace backward

* lisp/replace.el (query-replace-read-args): Split a non-negative arg
and a negative arg into separate elements.
(query-replace, query-replace-regexp, replace-string)
(replace-regexp): Add arg `backward'.  Doc fix.
(replace-match-maybe-edit): When new arg `backward' is non-nil,
move point to the beginning of the match.
(replace-search, replace-highlight): Use new arg `backward'
to set the value of `isearch-forward'.
(perform-replace): Add arg `backward' and use it to perform
replacement backward.

* lisp/isearch.el (isearch-query-replace): Use a negative prefix arg
to call `perform-replace' with a non-nil arg `backward'.

Fixes: debbugs:14979