bug#1744: bug-reference-mode doesn't fontify when called from mode hook

[Juri Linkov]

With the following mode hook:

  (add-hook 'change-log-mode-hook 'bug-reference-mode)

and a file local variable `bug-reference-url-format'
in the ChangeLog file:

;; Local Variables:
;; bug-reference-url-format: 
"http://emacsbugs.donarmstrong.com/cgi-bin/bugreport.cgi?bug=%s";
;; End:

bug references never get fontified because `bug-reference-mode' tests
whether a variable `bug-reference-url-format' is non-nil before calling
`(jit-lock-register #'bug-reference-fontify)' in `bug-reference-mode',
and this variable is not yet set because it gets initialized later
in `hack-local-variables' called after `set-auto-mode' in `normal-mode'.

-- 
Juri Linkov
http://www.jurta.org/emacs/