[gtk+] file chooser: Avoid triggering assertions

[Matthias Clasen <matthiasc src gnome org>]

commit 18de5e6547b1041c567212826c36fdbb74b80ba9
Author: Matthias Clasen <mclasen redhat com>
Date:   Mon Mar 2 15:53:35 2015 -0500

    file chooser: Avoid triggering assertions
    
    cairo surfaces are boxed types, so don't try to set them
    with g_value_set_object().

 gtk/gtkfilechooserwidget.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/gtk/gtkfilechooserwidget.c b/gtk/gtkfilechooserwidget.c
index 0f39ca2..71f1655 100644
--- a/gtk/gtkfilechooserwidget.c
+++ b/gtk/gtkfilechooserwidget.c
@@ -4030,7 +4030,7 @@ file_system_model_set (GtkFileSystemModel *model,
             }
         }
       else
-        g_value_set_object (value, NULL);
+        g_value_set_boxed (value, NULL);
       break;
     case MODEL_COL_SIZE:
       g_value_set_int64 (value, info ? g_file_info_get_size (info) : 0);