export and document handler:update-currently-open-files

gui-lib/framework/main.rkt

@@ -1094,6 +1094,20 @@ was never saved, then the first element of the list is @racket[#f].
   @{Sizes the @racket['framework:recently-opened-files/pos] preference list
     length to @racket[num].})
 
+ (proc-doc/names
+  handler:update-currently-open-files
+  (-> void?)
+  ()
+
+  @{
+This is called when new files are opened or when files
+are closed or when the frontmost window changes. As long as the app
+is not currently exiting, it updates the
+preference with the key @racket['framework:last-opened-files] to
+hold a list of list of paths, to record the lists of files that
+are currently open in tabs.
+})
+
  (proc-doc/names
   icon:get-paren-highlight-bitmap
   (-> (is-a?/c bitmap%))

gui-lib/framework/private/sig.rkt

@@ -289,7 +289,7 @@
      open-file
      install-recent-items
      add-to-recent
-     update-currently-open-files ;; not provided outside of the unit
+     update-currently-open-files
      set-recent-position
      set-recent-items-frame-superclass
      size-recently-opened-files))