Trait MessagePortMethods 
Source pub trait MessagePortMethods<D>{
    // Required methods
    fn PostMessage(
        &self,
        cx: JSContext,
        message: Handle<'_, Value>,
        transfer: CustomAutoRooterGuard<'_, Vec<*mut JSObject>>,
    ) -> Result<(), Error>;
    fn PostMessage_(
        &self,
        cx: JSContext,
        message: Handle<'_, Value>,
        options: RootedTraceableBox<StructuredSerializeOptions>,
    ) -> Result<(), Error>;
    fn Start(&self, _can_gc: CanGc);
    fn Close(&self, _can_gc: CanGc);
    fn GetOnmessage(&self, _can_gc: CanGc) -> Option<Rc<EventHandlerNonNull<D>>>;
    fn SetOnmessage(
        &self,
        value: Option<Rc<EventHandlerNonNull<D>>>,
        _can_gc: CanGc,
    );
    fn GetOnmessageerror(&self) -> Option<Rc<EventHandlerNonNull<D>>>;
    fn SetOnmessageerror(&self, value: Option<Rc<EventHandlerNonNull<D>>>);
    fn GetOnclose(&self) -> Option<Rc<EventHandlerNonNull<D>>>;
    fn SetOnclose(&self, value: Option<Rc<EventHandlerNonNull<D>>>);
}