[goffice] Fix critical in go_doc_finalize. [#628467]

[Jean Bréfort <jbrefort src gnome org>]

commit 68a1083193d0e66ced13ef20c4c5d1b8d2030b05
Author: Jean Brefort <jean brefort normalesup org>
Date:   Wed Sep 1 16:31:39 2010 +0200

    Fix critical in go_doc_finalize. [#628467]

 goffice/app/go-doc.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)
---
diff --git a/goffice/app/go-doc.c b/goffice/app/go-doc.c
index c812ddf..037981a 100644
--- a/goffice/app/go-doc.c
+++ b/goffice/app/go-doc.c
@@ -493,8 +493,10 @@ load_image_data (GsfXMLIn *xin, GsfXMLBlob *unknown)
 	 * harmful since the duplication will not survive
 	 * serialization. (Jean)
 	 */
-	if (real != image)
+	if (real != image) {
 		go_image_set_name (image, go_image_get_name (real));
+		g_object_unref (image);
+	}
 	g_object_set_data (G_OBJECT (doc), "new image", NULL);
 }