Improve some webdriver conformance tests results (#36673)

These changes allow test_dom_token_list from
/execute_script/collections.py to pass, and various tests in
/execute_script/arguments.py to expose new failures.

Testing: Not run in CI yet, but verified results from
tests/wpt/tests/webdriver/tests/classic/{execute_script,execute_async_script}
locally.
Fixes: #35738

---------

Signed-off-by: Josh Matthews <josh@joshmatthews.net>

components/script/dom/window.rs

@@ -65,6 +65,7 @@ use profile_traits::time::ProfilerChan as TimeProfilerChan;
 use script_bindings::codegen::GenericBindings::NavigatorBinding::NavigatorMethods;
 use script_bindings::codegen::GenericBindings::PerformanceBinding::PerformanceMethods;
 use script_bindings::interfaces::WindowHelpers;
+use script_bindings::root::Root;
 use script_layout_interface::{
     FragmentType, Layout, PendingImageState, QueryMsg, Reflow, ReflowGoal, ReflowRequest,
     TrustedNodeAddress, combine_id_with_fragment_type,
@@ -146,6 +147,7 @@ use crate::dom::performance::Performance;
 use crate::dom::promise::Promise;
 use crate::dom::screen::Screen;
 use crate::dom::selection::Selection;
+use crate::dom::shadowroot::ShadowRoot;
 use crate::dom::storage::Storage;
 #[cfg(feature = "bluetooth")]
 use crate::dom::testrunner::TestRunner;
@@ -165,7 +167,7 @@ use crate::script_runtime::{CanGc, JSContext, Runtime};
 use crate::script_thread::ScriptThread;
 use crate::timers::{IsInterval, TimerCallback};
 use crate::unminify::unminified_path;
-use crate::webdriver_handlers::jsval_to_webdriver;
+use crate::webdriver_handlers::{find_node_by_unique_id_in_document, jsval_to_webdriver};
 use crate::{fetch, window_named_properties};
 
 /// A callback to call when a response comes back from the `ImageCache`.
@@ -1394,6 +1396,30 @@ impl WindowMethods<crate::DomTypeHolder> for Window {
         }
     }
 
+    fn WebdriverElement(&self, id: DOMString) -> Option<DomRoot<Element>> {
+        find_node_by_unique_id_in_document(&self.Document(), id.into())
+            .ok()
+            .and_then(Root::downcast)
+    }
+
+    fn WebdriverFrame(&self, id: DOMString) -> Option<DomRoot<Element>> {
+        find_node_by_unique_id_in_document(&self.Document(), id.into())
+            .ok()
+            .and_then(Root::downcast::<HTMLIFrameElement>)
+            .map(Root::upcast::<Element>)
+    }
+
+    fn WebdriverWindow(&self, _id: DOMString) -> Option<DomRoot<Window>> {
+        warn!("Window references are not supported in webdriver yet");
+        None
+    }
+
+    fn WebdriverShadowRoot(&self, id: DOMString) -> Option<DomRoot<ShadowRoot>> {
+        find_node_by_unique_id_in_document(&self.Document(), id.into())
+            .ok()
+            .and_then(Root::downcast)
+    }
+
     // https://drafts.csswg.org/cssom/#dom-window-getcomputedstyle
     fn GetComputedStyle(
         &self,

components/script/webdriver_handlers.rs

@@ -53,6 +53,7 @@ use crate::dom::bindings::inheritance::Castable;
 use crate::dom::bindings::reflector::{DomGlobal, DomObject};
 use crate::dom::bindings::root::DomRoot;
 use crate::dom::bindings::str::DOMString;
+use crate::dom::document::Document;
 use crate::dom::element::Element;
 use crate::dom::eventtarget::EventTarget;
 use crate::dom::globalscope::GlobalScope;
@@ -77,12 +78,27 @@ fn find_node_by_unique_id(
     pipeline: PipelineId,
     node_id: String,
 ) -> Result<DomRoot<Node>, ErrorStatus> {
-    match documents.find_document(pipeline).and_then(|document| {
-        document
-            .upcast::<Node>()
-            .traverse_preorder(ShadowIncluding::Yes)
-            .find(|node| node.unique_id() == node_id)
-    }) {
+    match documents.find_document(pipeline) {
+        Some(doc) => find_node_by_unique_id_in_document(&doc, node_id),
+        None => {
+            if ScriptThread::has_node_id(&node_id) {
+                Err(ErrorStatus::StaleElementReference)
+            } else {
+                Err(ErrorStatus::NoSuchElement)
+            }
+        },
+    }
+}
+
+pub(crate) fn find_node_by_unique_id_in_document(
+    document: &Document,
+    node_id: String,
+) -> Result<DomRoot<Node>, ErrorStatus> {
+    match document
+        .upcast::<Node>()
+        .traverse_preorder(ShadowIncluding::Yes)
+        .find(|node| node.unique_id() == node_id)
+    {
         Some(node) => Ok(node),
         None => {
             if ScriptThread::has_node_id(&node_id) {