Update serialization steps for return value of "browsingContext.locateNodes" command

Author: lutien

index.bs

@@ -3174,9 +3174,15 @@ The [=remote end steps=] with |session| and |command parameters| are:
    let |result ownership| be |command parameters|["<code>ownership</code>"].
    Otherwise, let |result ownership| be "none".
 
-1. Let |serialized nodes| be the result of [=serialize as a remote value=] with
-   |result nodes|, |serialization options|, |result ownership|, a new [=/map=]
-   as serialization internal map, |realm| and |session|.
+1. Let |serialized nodes| be an empty [=/list=].
+
+1. For each |result node| in |result nodes|:
+
+   1. Let |serialized node| be the result of [=serialize as a remote value=] with
+      |result node|, |serialization options|, |result ownership|, a new [=/map=]
+      as serialization internal map, |realm| and |session|.
+
+   1. [=list/Append=] |serialized node| to |serialized nodes|.
 
 1. Let |result| be a [=/map=] matching the <code>browsingContext.LocateNodesResult</code>
    production, with the <code>nodes</code> field set |serialized nodes|.