Review EVAL_FLAG_BLAME_PARENT

[hostilefork]

This flag was not used, and eval flags are in short supply...so it was reclaimed. But was the purpose it served still applicable?

//=//// EVAL_FLAG_BLAME_PARENT ////////////////////////////////////////////=//
//
// Marks an error to hint that a frame is internal, and that reporting an
// error on it probably won't give a good report.