The alias of obsolete variable font-lock-reference-face will be finally dropped.

[Takesi Ayanokoji]

Hello,

The codes of po-mode.el refers obsolete variable font-lock-reference-face, currently.

This works fine in the current release version of Emacs(Emacs 28.x), because this version refers font-lock-reference-face by using aliasing-mechanism to refer obsolete variables.

But in the next release of Emacs(Emacs 29), this work around will be dropped(https://git.savannah.gnu.org/cgit/emacs.git/diff/lisp/font-lock.el?h=emacs-29&id=107f832577123ea7ebe867cba55601d0142f546f), so po-mode.el should be update to use new variable, font-lock-constant-face.

Thanks.

---

diff --git a/gettext-tools/emacs/po-mode.el b/gettext-tools/emacs/po-mode.el

index e04428772..162e18f63 100644

--- a/gettext-tools/emacs/po-mode.el

+++ b/gettext-tools/emacs/po-mode.el

@@ -909,7 +909,7 @@ M-S  Ignore path          M-A  Ignore PO file      *M-L  Ignore lexicon

 (defconst po-font-lock-keywords

   '(

     ("^# .*\\|^#[:,]?" . font-lock-comment-face)

-    ("^#:\\(.*\\)" 1 font-lock-reference-face)

+    ("^#:\\(.*\\)" 1 font-lock-constant-face)

     ("^#,\\(.*\\)" 1 font-lock-function-name-face)

     ("^\\(\\(msg\\(ctxt\\|id\\(_plural\\)?\\|str\\(\\[[0-9]\\]\\)?\\)\\) \\)?\"\\|\"$"

      . font-lock-keyword-face)