IDData* data;
IDData* data=NULL;
xpc_JSObjectToID(JSContext *cx, JSObject* obj){    IDData* data;    if(!cx || !obj ||       !JS_InstanceOf(cx, obj, &nsID_class, NULL) ||       !(data = (IDData*) JS_GetPrivate(cx, obj)))        return NULL;    return &data->GetID();}