[gtk] filechooserentry: Correctly annotate a return value as (nullable)

[Timm Bäder <baedert src gnome org>]

commit 23ddac2e72baf5c03b4abf3731f95ec3b955b786
Author: Timm Bäder <tbaeder redhat com>
Date:   Fri May 24 08:47:40 2019 +0200

    filechooserentry: Correctly annotate a return value as (nullable)

 gtk/gtkfilechooserentry.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)
---
diff --git a/gtk/gtkfilechooserentry.c b/gtk/gtkfilechooserentry.c
index 56bd9e9b56..ef193d1357 100644
--- a/gtk/gtkfilechooserentry.c
+++ b/gtk/gtkfilechooserentry.c
@@ -906,8 +906,9 @@ _gtk_file_chooser_entry_set_base_folder (GtkFileChooserEntry *chooser_entry,
  * be different.  If the user has entered unparsable text, or text which
  * the entry cannot handle, this will return %NULL.
  *
- * Returns: the file for the current folder - you must g_object_unref()
- *   the value after use.
+ * Returns: (nullable): the file for the current folder or %NULL if the
+ *   current folder can not be determined. Unref the file with
+ *   g_object_unref() after use.
  **/
 GFile *
 _gtk_file_chooser_entry_get_current_folder (GtkFileChooserEntry *chooser_entry)