Remove `org-inhibit-invisibility'

* lisp/org-macs.el (org-inhibit-invisibility): Remove function.
* lisp/org.el (org-set-tags): Apply removal.

lisp/org-macs.el

@@ -188,12 +188,6 @@ program is needed for, so that the error message can be more informative."
 	(error "Can't find `%s'%s" cmd
 	       (if use (format " (%s)" use) "")))))
 
-(defsubst org-inhibit-invisibility ()
-  "Modified `buffer-invisibility-spec' for Emacs 21.
-Some ops with invisible text do not work correctly on Emacs 21.  For these
-we turn off invisibility temporarily.  Use this in a `let' form."
-  (if (< emacs-major-version 22) nil buffer-invisibility-spec))
-
 (defsubst org-last (list)
   "Return the last element of LIST."
   (car (last list)))

lisp/org.el

@@ -15025,10 +15025,9 @@ When JUST-ALIGN is non-nil, only align tags."
       (if arg
           (save-excursion
             (goto-char (point-min))
-            (let ((buffer-invisibility-spec (org-inhibit-invisibility)))
-              (while (re-search-forward org-outline-regexp-bol nil t)
-                (org-set-tags nil t)
-                (end-of-line)))
+            (while (re-search-forward org-outline-regexp-bol nil t)
+	      (org-set-tags nil t)
+	      (end-of-line))
             (message "All tags realigned to column %d" org-tags-column))
 	(let* ((current (org-get-tags-string))
 	       (col (current-column))