Auto merge of #22669 - georgeroman:ignore_children_of_void_when_serializing, r=jdm

Ignore children of void elements when serializing

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #22607

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components/script/dom/servoparser/html.rs

@@ -153,6 +153,10 @@ struct SerializationIterator {
 }
 
 fn rev_children_iter(n: &Node) -> impl Iterator<Item = DomRoot<Node>> {
+    if n.downcast::<Element>().map_or(false, |e| e.is_void()) {
+        return Node::new_document_node().rev_children();
+    }
+
     match n.downcast::<HTMLTemplateElement>() {
         Some(t) => t.Content().upcast::<Node>().rev_children(),
         None => n.rev_children(),
@@ -210,12 +214,6 @@ impl<'a> Serialize for &'a Node {
     ) -> io::Result<()> {
         let node = *self;
 
-        if let TraversalScope::ChildrenOnly(_) = traversal_scope {
-            if node.downcast::<Element>().map_or(false, |e| e.is_void()) {
-                return Ok(());
-            }
-        }
-
         let iter = SerializationIterator::new(node, traversal_scope != IncludeNode);
 
         for cmd in iter {