[gthumb] fixed error when loading the active filter file

[Paolo Bacchilega <paobac src gnome org>]

commit b9ea2a7f7a5d1b47b80300fff82c215aa9244f0d
Author: Paolo Bacchilega <paobac src gnome org>
Date:   Sun May 13 19:39:49 2012 +0200

    fixed error when loading the active filter file
    
    check whether the buffer is null before using it

 gthumb/gth-filterbar.c |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)
---
diff --git a/gthumb/gth-filterbar.c b/gthumb/gth-filterbar.c
index a0eabab..fcaacb3 100644
--- a/gthumb/gth-filterbar.c
+++ b/gthumb/gth-filterbar.c
@@ -533,6 +533,11 @@ gth_filterbar_load_filter (GthFilterbar *filterbar,
 		return;
 	}
 
+	if (buffer == NULL) {
+		g_object_unref (filter_file);
+		return;
+	}
+
 	doc = dom_document_new ();
 	if (dom_document_load (doc, buffer, len, NULL)) {
 		DomElement *node = DOM_ELEMENT (doc)->first_child;