bug#46469: 27.1; `isearch-del-char' should move point further back

[Augusto Stoffel]

Suppose my buffer contains the text "x1yx2" right after point, and that
`isearch-del-char' is bound to DEL in Isearch mode.  If I type

   C-s y DEL x1

then I would expect the search to succeed: the cursor would first go
after "y", then return to the starting point of search after pressing
DEL – this is how `isearch-delete-char' behaves, anyway.

Instead, the cursor remains after "y" after pressing DEL, and the search
fails with the cursor after the second "x".  I have attached a patch to
fix this.

I have also attached a second trivial patch for an unrelated, very tiny
bug.

Best,
Augusto

0002-Make-isearch-del-char-backtrack-the-search-more-aggr.patch
Description: Text Data

0001-Small-correction-to-isearch-lazy-highlight-buffer-up.patch
Description: Text Data