[gtk+] Add a configure check for new enough gettext

[Matthias Clasen <matthiasc src gnome org>]

commit c951740cf9cd12bf8f6d7ddb383eb39cc58fb3b7
Author: Matthias Clasen <mclasen redhat com>
Date:   Thu Feb 26 19:00:24 2015 -0500

    Add a configure check for new enough gettext
    
    Check that xgettext understands glade files.

 configure.ac |    9 +++++++++
 1 files changed, 9 insertions(+), 0 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 3200d4b..839d9f0 100644
--- a/configure.ac
+++ b/configure.ac
@@ -665,6 +665,15 @@ fi
 # i18n stuff
 ALL_LINGUAS="`grep -v '^#' "$srcdir/po/LINGUAS" | tr '\n' ' '`"
 AM_GLIB_GNU_GETTEXT
+
+AC_MSG_CHECKING([whether xgettext supports ui files])
+if $ac_cv_path_XGETTEXT --language=Glade $srcdir/gtk/ui/gtkfilechooserwidget.ui > /dev/null 2>&1; then
+  AC_MSG_RESULT([yes])
+else
+  AC_MSG_RESULT([no])
+  AC_MSG_ERROR([GNU gettext 0.18.3 or newer is required])
+fi
+
 LIBS="$LIBS $INTLLIBS"
 AC_CONFIG_COMMANDS([po-properties],
                    [[case "$CONFIG_FILES" in *po-properties/Makefile.in*)