Obsolete code in savehist

[Juanma Barranquero]

Wouldn't be about time to remove this code from savehist-save?

      ;; During the 24.3 development, read-passwd had a bug which resulted in
      ;; the passwords being saved by savehist.  Trim them, retroactively.
      ;; This code can be removed after the 24.3 release.
      (dolist (sym savehist-minibuffer-history-variables)
        (if (and (symbolp sym) (equal (symbol-name sym) "forget-history"))
            (setq savehist-minibuffer-history-variables
                  (delq sym savehist-minibuffer-history-variables))))