[glib/wip/baedert/keyfile] keyfile: Delay calling g_get_language_names() until it's needed

[Timm Bäder <baedert src gnome org>]

commit 037f1ce672a54c0ad62bd0dd72a64663c93c7f61
Author: Timm Bäder <mail baedert org>
Date:   Tue Dec 29 08:35:36 2020 +0100

    keyfile: Delay calling g_get_language_names() until it's needed
    
    The g_get_languages() call is quite costly and often unneeded.

 glib/gkeyfile.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)
---
diff --git a/glib/gkeyfile.c b/glib/gkeyfile.c
index bbe638b74..8fc0322e8 100644
--- a/glib/gkeyfile.c
+++ b/glib/gkeyfile.c
@@ -510,6 +510,7 @@ struct _GKeyFile
 
   GKeyFileFlags flags;
 
+  gboolean checked_locales;
   gchar **locales;
 
   gint ref_count;  /* (atomic) */
@@ -635,7 +636,6 @@ g_key_file_init (GKeyFile *key_file)
   key_file->parse_buffer = g_string_sized_new (128);
   key_file->list_separator = ';';
   key_file->flags = 0;
-  key_file->locales = g_strdupv ((gchar **)g_get_language_names ());
 }
 
 static void
@@ -1232,6 +1232,12 @@ g_key_file_locale_is_interesting (GKeyFile    *key_file,
   if (key_file->flags & G_KEY_FILE_KEEP_TRANSLATIONS)
     return TRUE;
 
+  if (!key_file->checked_locales && !key_file->locales)
+    {
+      key_file->locales = g_strdupv ((gchar **)g_get_language_names ());
+      key_file->checked_locales = TRUE;
+    }
+
   for (i = 0; key_file->locales[i] != NULL; i++)
     {
       if (g_ascii_strcasecmp (key_file->locales[i], locale) == 0)