Auto merge of #6507 - Ms2ger:node-insert, r=Manishearth

Fix a bug in Node::pre_insert.

It was accidentally broken in 3ce368fa289bc4c6d09b23357350a37b861013f9.

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1 files changed, 6 insertions, 3 deletions

diff --git a/components/script/dom/node.rs b/components/script/dom/node.rs
index 83244f554b9..35c07308a08 100644
--- a/components/script/dom/node.rs
+++ b/components/script/dom/node.rs
@@ -1626,11 +1626,14 @@ impl Node {
         }
 
         // Step 7-8.
+        let reference_child_root;
         let reference_child = match child {
-            Some(child) if child == node => node.GetNextSibling(),
-            _ => None
+            Some(child) if child == node => {
+                reference_child_root = node.GetNextSibling();
+                reference_child_root.r()
+            },
+            _ => child
         };
-        let reference_child = reference_child.r().or(child);
 
         // Step 9.
         let document = document_from_node(parent);