bug#10049: 24.0.91; Setting generated-autoload-file as local variable not working correctly

[David Engster <deng@randomsample.de>]

Recipe:

* Create file 'testautoload.el' in /home/whatever/test containing

--------------------
;;;###autoload
(defun testautoload-testfunc ())

;; Local variables:
;; generated-autoload-file: "foo.el"
;; End:
--------------------

* Now create autoload file using (all in one line)

emacs --batch -l autoload -f toggle-debug-on-error
   --eval '(setq generated-autoload-file "/home/whatever/test/foo.el")' 
   -f batch-update-autoloads /home/whatever/test

You'll see:
...
Wrote /home/whatever/test/foo.el
Making generated-autoload-file local to  *autoload-file* while let-bound!
Generating autoloads for testautoload.el...
Generating autoloads for testautoload.el...done
Saving file /home/void/test/foo.el...
Wrote /home/void/test/foo.el
(No changes need to be saved)

and the file foo.el will be generated (BTW, shouldn't the above
*autoload-file* better denote the actual file name?)

* Now simply call the above command again. You'll get:

Debugger entered--Lisp error: (wrong-type-argument listp "77d69bf537d61f438126776e130fef3d")
  time-less-p("77d69bf537d61f438126776e130fef3d" (20161 36303))
  update-directory-autoloads("/home/whatever/test")
  apply(update-directory-autoloads "/home/whatever/test")
  batch-update-autoloads()
[...]

This is due to the following autoload header in foo.el:

;;;### (autoloads (testautoload-testfunc) "testautoload" "testautoload.el"
;;;;;;  "77d69bf537d61f438126776e130fef3d")
;;; Generated autoloads from testautoload.el

where the md5-looking hex-string is obviously not a time.