master 3832241: Revert "* lisp/image-dired.el: Remove unnecessary 'declare-function'."

[Stefan Kangas]

branch: master
commit 38322419e4d32ff9f3d5505360f2714c31aa2e8d
Author: Stefan Kangas <stefan@marxist.se>
Commit: Stefan Kangas <stefan@marxist.se>

    Revert "* lisp/image-dired.el: Remove unnecessary 'declare-function'."
    
    This reverts commit e0261d4a0cf2a23d32b51b84870a3a75f8273c7c.
    
    This commit gives warnings on builds --without-x.
    Problem pointed out by Glenn Morris <rgm@gnu.org> in:
    https://lists.gnu.org/r/emacs-devel/2021-11/msg01278.html
---
 lisp/image-dired.el | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lisp/image-dired.el b/lisp/image-dired.el
index 047be5a..852ef0f 100644
--- a/lisp/image-dired.el
+++ b/lisp/image-dired.el
@@ -1739,6 +1739,8 @@ Note that n, p and <down> and <up> will be hijacked and 
bound to
 `image-dired-dired-next-line' and `image-dired-dired-previous-line'."
   :keymap image-dired-minor-mode-map)
 
+(declare-function clear-image-cache "image.c" (&optional filter))
+
 (defun image-dired-create-thumbs (&optional arg)
   "Create thumbnail images for all marked files in Dired.
 With prefix argument ARG, create thumbnails even if they already exist