Auto merge of #25548 - pshaughn:docnamedgetter, r=jdm

Add SupportedPropertyNames to Document (also fix iframe getting)

Existing test of named-getting an iframe now succeeds. I added a new test for Object.getOwnPropertyNames(document) based on my understanding of the spec; that test could use a second opinion.

UPDATE: This was trying to do too many things in one PR as originally submitted. It is now using #25572 as a base, and I suggest reviewing that PR before this one to avoid duplicating review effort.

---
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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 #7273 for all implemented named getters, fix #25146, and fix the iframe case only of #25145.

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- [X] There are tests for these changes

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components/script/dom/node.rs

@@ -85,6 +85,7 @@ use script_traits::UntrustedNodeAddress;
 use selectors::matching::{matches_selector_list, MatchingContext, MatchingMode};
 use selectors::parser::SelectorList;
 use servo_arc::Arc;
+use servo_atoms::Atom;
 use servo_url::ServoUrl;
 use smallvec::SmallVec;
 use std::borrow::ToOwned;
@@ -1212,6 +1213,34 @@ impl Node {
             );
         }
     }
+
+    // https://html.spec.whatwg.org/multipage/#dom-document-nameditem-filter
+    pub fn is_document_named_item(&self, name: &Atom) -> bool {
+        let html_elem_type = match self.type_id() {
+            NodeTypeId::Element(ElementTypeId::HTMLElement(type_)) => type_,
+            _ => return false,
+        };
+        let elem = self
+            .downcast::<Element>()
+            .expect("Node with an Element::HTMLElement NodeTypeID must be an Element");
+        match html_elem_type {
+            HTMLElementTypeId::HTMLFormElement | HTMLElementTypeId::HTMLIFrameElement => {
+                elem.get_name().map_or(false, |n| n == *name)
+            },
+            HTMLElementTypeId::HTMLImageElement =>
+            // Images can match by id, but only when their name is non-empty.
+            {
+                elem.get_name().map_or(false, |n| {
+                    n == *name || elem.get_id().map_or(false, |i| i == *name)
+                })
+            },
+            // TODO: Handle <embed> and <object>; these depend on
+            // whether the element is "exposed", a concept which
+            // doesn't fully make sense until embed/object behaviors
+            // are actually implemented.
+            _ => false,
+        }
+    }
 }
 
 /// Iterate through `nodes` until we find a `Node` that is not in `not_in`