Auto merge of #22542 - georgeroman:serialize_children_of_void_as_empty_strings, r=jdm

Serialize the children of void html elements as empty strings

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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 #22502  (GitHub issue number if applicable)

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1 files changed, 6 insertions, 0 deletions

diff --git a/components/script/dom/servoparser/html.rs b/components/script/dom/servoparser/html.rs
index 3ebf4b391b6..62fe26153ed 100644
--- a/components/script/dom/servoparser/html.rs
+++ b/components/script/dom/servoparser/html.rs
@@ -210,6 +210,12 @@ 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 {