[gtk+/gtk-2-24] Avoid a crash in the pixbuf engine

[Matthias Clasen <matthiasc src gnome org>]

commit 9559c707d59c5e5c34596f8f75c7ed0b97b4a196
Author: Matthias Clasen <mclasen redhat com>
Date:   Sun Dec 1 17:10:31 2013 -0500

    Avoid a crash in the pixbuf engine
    
    This is fallout from e4c83bbfdb60fdfe0bae207b1ddae295dc267a23,
    which removed a necessary check.

 modules/engines/pixbuf/pixbuf-rc-style.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/modules/engines/pixbuf/pixbuf-rc-style.c b/modules/engines/pixbuf/pixbuf-rc-style.c
index abff64d..a3443d2 100644
--- a/modules/engines/pixbuf/pixbuf-rc-style.c
+++ b/modules/engines/pixbuf/pixbuf-rc-style.c
@@ -803,7 +803,7 @@ theme_parse_image(GtkSettings  *settings,
   if (data->overlay && !data->overlay->filename)
     clear_theme_pixbuf_and_warn (&data->overlay, scanner, "Overlay image options specified without 
filename");
 
-  if (!data->gap->filename)
+  if (data->gap && !data->gap->filename)
     {
       if (data->gap)
         clear_theme_pixbuf_and_warn (&data->gap, scanner, "Gap image options specified without filename");