Auto merge of #22743 - ferjm:shadowdom, r=emilio

Partial ShadowDOM support

This is just an early WIP, not to take it very seriously yet.

- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [x] These changes fix #22719
- [x] There are tests for these changes

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1 files changed, 2 insertions, 2 deletions

diff --git a/components/script/dom/htmllabelelement.rs b/components/script/dom/htmllabelelement.rs
index 3c9106a589a..11ee09bce94 100644
--- a/components/script/dom/htmllabelelement.rs
+++ b/components/script/dom/htmllabelelement.rs
@@ -15,7 +15,7 @@ use crate::dom::event::Event;
 use crate::dom::eventtarget::EventTarget;
 use crate::dom::htmlelement::HTMLElement;
 use crate::dom::htmlformelement::{FormControl, FormControlElementHelpers, HTMLFormElement};
-use crate::dom::node::{document_from_node, Node};
+use crate::dom::node::{document_from_node, Node, ShadowIncluding};
 use crate::dom::virtualmethods::VirtualMethods;
 use dom_struct::dom_struct;
 use html5ever::{LocalName, Prefix};
@@ -162,7 +162,7 @@ impl VirtualMethods for HTMLLabelElement {
 impl HTMLLabelElement {
     pub fn first_labelable_descendant(&self) -> Option<DomRoot<HTMLElement>> {
         self.upcast::<Node>()
-            .traverse_preorder()
+            .traverse_preorder(ShadowIncluding::No)
             .filter_map(DomRoot::downcast::<HTMLElement>)
             .filter(|elem| elem.is_labelable_element())
             .next()