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, 9 insertions, 6 deletions

diff --git a/components/script/dom/htmliframeelement.rs b/components/script/dom/htmliframeelement.rs
index 24cea710450..a85b9bfa915 100644
--- a/components/script/dom/htmliframeelement.rs
+++ b/components/script/dom/htmliframeelement.rs
@@ -19,7 +19,9 @@ use crate::dom::element::{AttributeMutation, Element, RawLayoutElementHelpers};
 use crate::dom::eventtarget::EventTarget;
 use crate::dom::globalscope::GlobalScope;
 use crate::dom::htmlelement::HTMLElement;
-use crate::dom::node::{document_from_node, window_from_node, Node, NodeDamage, UnbindContext};
+use crate::dom::node::{
+    document_from_node, window_from_node, BindContext, Node, NodeDamage, UnbindContext,
+};
 use crate::dom::virtualmethods::VirtualMethods;
 use crate::dom::window::ReflowReason;
 use crate::dom::windowproxy::WindowProxy;
@@ -584,7 +586,7 @@ impl VirtualMethods for HTMLIFrameElement {
                 // may be in a different script thread. Instread, we check to see if the parent
                 // is in a document tree and has a browsing context, which is what causes
                 // the child browsing context to be created.
-                if self.upcast::<Node>().is_in_doc_with_browsing_context() {
+                if self.upcast::<Node>().is_connected_with_browsing_context() {
                     debug!("iframe src set while in browsing context.");
                     self.process_the_iframe_attributes(ProcessingMode::NotFirstTime);
                 }
@@ -610,11 +612,12 @@ impl VirtualMethods for HTMLIFrameElement {
         }
     }
 
-    fn bind_to_tree(&self, tree_in_doc: bool) {
+    fn bind_to_tree(&self, context: &BindContext) {
         if let Some(ref s) = self.super_type() {
-            s.bind_to_tree(tree_in_doc);
+            s.bind_to_tree(context);
         }
 
+        let tree_connected = context.tree_connected;
         let iframe = Trusted::new(self);
         document_from_node(self).add_delayed_task(task!(IFrameDelayedInitialize: move || {
             let this = iframe.root();
@@ -624,9 +627,9 @@ impl VirtualMethods for HTMLIFrameElement {
             // browsing context, set the element's nested browsing context
             // to the newly-created browsing context, and then process the
             // iframe attributes for the "first time"."
-            if this.upcast::<Node>().is_in_doc_with_browsing_context() {
+            if this.upcast::<Node>().is_connected_with_browsing_context() {
                 debug!("iframe bound to browsing context.");
-                debug_assert!(tree_in_doc, "is_in_doc_with_bc, but not tree_in_doc");
+                debug_assert!(tree_connected, "is_connected_with_bc, but not tree_connected");
                 this.create_nested_browsing_context();
                 this.process_the_iframe_attributes(ProcessingMode::FirstTime);
             }