[gtk+] filechooserbutton: Remove unnecessary declaration

[Emmanuele Bassi <ebassi src gnome org>]

commit e75bbafeacb91252a5f30e3da0cb2e6fd1ad71a2
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Sat Oct 15 21:30:27 2016 +0100

    filechooserbutton: Remove unnecessary declaration

 gtk/gtkfilechooserbutton.c |    2 --
 1 files changed, 0 insertions(+), 2 deletions(-)
---
diff --git a/gtk/gtkfilechooserbutton.c b/gtk/gtkfilechooserbutton.c
index d201db9..2a07563 100644
--- a/gtk/gtkfilechooserbutton.c
+++ b/gtk/gtkfilechooserbutton.c
@@ -1933,8 +1933,6 @@ model_add_volumes (GtkFileChooserButton *button,
     }
 }
 
-extern gchar * _gtk_file_chooser_label_for_file (GFile *file);
-
 static void
 model_add_bookmarks (GtkFileChooserButton *button,
                     GSList               *bookmarks)