Add top-level creation URL for global scope (#37342)

Global scopes have two creation URLs: one for itself and one for the
"top-level" scope. It's not immediately obvious what is considered
top-level here (it is not strictly defined in the specification).

In any case, reports need the creation URL of the scope itself, not the
top-level version. Therefore, propagate this information from all
scopes, where the worker and worklets remain to pass in `None` for their
top-level scope.

Part of #37328

---------

Signed-off-by: Tim van der Lippe <tvanderlippe@gmail.com>

components/script/script_thread.rs

@@ -3395,6 +3395,11 @@ impl ScriptThread {
             incomplete.viewport_details,
             origin.clone(),
             final_url.clone(),
+            // TODO(37417): Set correct top-level URL here. Currently, we only specify the
+            // url of the current window. However, in case this is an iframe, we should
+            // pass in the URL from the frame that includes the iframe (which potentially
+            // is another nested iframe in a frame).
+            final_url.clone(),
             incomplete.navigation_start,
             self.webgl_chan.as_ref().map(|chan| chan.channel()),
             #[cfg(feature = "webxr")]