[lasem] dom_node: allow NULL as new_child in insert_before.

[Emmanuel Pacaud <emmanuel src gnome org>]

commit 3360bb23082640ea193c856d40d800b7913d6687
Author: Emmanuel Pacaud <emmanuel gnome org>
Date:   Sun Nov 14 18:23:34 2010 +0100

    dom_node: allow NULL as new_child in insert_before.

 src/lsmdomnode.c |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)
---
diff --git a/src/lsmdomnode.c b/src/lsmdomnode.c
index cc4101b..673f942 100644
--- a/src/lsmdomnode.c
+++ b/src/lsmdomnode.c
@@ -223,6 +223,11 @@ lsm_dom_node_replace_child (LsmDomNode* self, LsmDomNode* new_child, LsmDomNode*
 
 	lsm_dom_node_remove_child (self, old_child);
 
+	if (new_child == NULL)
+		return NULL;
+
+	g_return_val_if_fail (LSM_IS_DOM_NODE (new_child), NULL);
+
 	if (next_sibling == NULL)
 		return lsm_dom_node_append_child (self, new_child);
 	else