[gtk+] icontheme: Avoid a crash

[Matthias Clasen <matthiasc src gnome org>]

commit e54549502e3b0b1bd8b01fc7de9c44a339e4437c
Author: Matthias Clasen <mclasen redhat com>
Date:   Fri Jan 29 23:36:24 2016 -0500

    icontheme: Avoid a crash
    
    gtk_icon_info_new_for_file with a size of 0 would fail for
    symbolic pngs because we ended up scaling with 0. Avoid this.

 gtk/gtkicontheme.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/gtk/gtkicontheme.c b/gtk/gtkicontheme.c
index 0a04258..d7dc371 100644
--- a/gtk/gtkicontheme.c
+++ b/gtk/gtkicontheme.c
@@ -3949,7 +3949,7 @@ icon_info_ensure_scale_and_pixbuf (GtkIconInfo *icon_info)
     icon_info->scale = image_size / 1000.;
   else if (icon_info->scale < 0.0)
     {
-      if (image_size > 0)
+      if (image_size > 0 && scaled_desired_size > 0)
         icon_info->scale = (gdouble)scaled_desired_size / (gdouble)image_size;
       else
         icon_info->scale = 1.0;