script: Pass &mut JSContext to reflect_node_with_proto (#43952)

A lot (and I mean, really a lot) depends on these constructors.
Therefore, this is the one spaghetti ball that I could extract and
convert all `can_gc` to `cx`. There are some new introductions of
`temp_cx` in the callbacks of the servo parser, but we already had some
in other callbacks.

Part of #40600

Testing: It compiles

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

components/script/dom/html/htmliframeelement.rs

@@ -692,19 +692,19 @@ impl HTMLIFrameElement {
     }
 
     pub(crate) fn new(
+        cx: &mut js::context::JSContext,
         local_name: LocalName,
         prefix: Option<Prefix>,
         document: &Document,
         proto: Option<HandleObject>,
-        can_gc: CanGc,
     ) -> DomRoot<HTMLIFrameElement> {
         Node::reflect_node_with_proto(
+            cx,
             Box::new(HTMLIFrameElement::new_inherited(
                 local_name, prefix, document,
             )),
             document,
             proto,
-            can_gc,
         )
     }