[gtk+] appchooserdialog: Remove unused macro

[Timm Bäder <baedert src gnome org>]

commit 3515a27f8e8e02f9daba1e0f1c40422fa21b9585
Author: Timm Bäder <mail baedert org>
Date:   Tue Oct 3 17:59:47 2017 +0200

    appchooserdialog: Remove unused macro

 gtk/gtkappchooserdialog.c |    2 --
 1 files changed, 0 insertions(+), 2 deletions(-)
---
diff --git a/gtk/gtkappchooserdialog.c b/gtk/gtkappchooserdialog.c
index ee33f0f..4053088 100644
--- a/gtk/gtkappchooserdialog.c
+++ b/gtk/gtkappchooserdialog.c
@@ -63,8 +63,6 @@
 #include <glib/gi18n-lib.h>
 #include <gio/gio.h>
 
-#define sure_string(s) ((const char *) ((s) != NULL ? (s) : ""))
-
 struct _GtkAppChooserDialogPrivate {
   char *content_type;
   GFile *gfile;