Jacek Caban (@jacek) commented about dlls/mshtml/tests/script.c:
VARIANT v;hres = IHTMLDocument2_get_parentWindow(notif_doc, &window);ok(hres == S_OK, "get_parentWindow failed: %08lx\n", hres);hres = IHTMLWindow2_get_document(window, &doc_node);IHTMLWindow2_Release(window);ok(hres == S_OK, "get_document failed: %08lx\n", hres);V_VT(&v) = VT_EMPTY;V_I4(&v) = 1234;hres = IHTMLDocument2_Invoke(doc_node, DISPID_READYSTATE, &IID_NULL, 0, DISPATCH_PROPERTYGET, &dp, &v, NULL, NULL);ok(hres == S_OK, "Invoke(DISPID_READYSTATE) failed: %08lx\n", hres);ok(V_VT(&v) == VT_I4, "V_VT(v) = %d\n", V_VT(&v));IHTMLDocument2_Release(doc_node);- }
 
This place seems a bit random for the test, maybe something like `PropertyNotifySink_OnChanged` would work?