bug#35326: 26.1; vc-git-grep should pass -i like isearch

[Juri Linkov <juri@linkov.net>]

>> PS: Regarding -w that I proposed previously, I could create
>> a separate request, but here is a preliminary version:
>
> [...]
>
>> +                           (when grep-word-search
>> +                             (push "-w" opts))
>
> Hm...  I always just say \bfoo\b when I want the word-ish version, so I
> don't know whether this really warrants a new command.

OK, a new request could be created later on more demand.
Meanwhile, I'm using this short snippet in ~/.emacs:

  (defun wrgrep ()
    "Word-based version of `rgrep'.
  Modifies the grep-find template to add the option `-w' that matches whole words."
    (interactive)
    (let ((grep-host-defaults-alist nil)
          (grep-find-template
           (replace-regexp-in-string "<C>" "-w \\&" grep-find-template)))
      (call-interactively 'rgrep)))