bug#19711: 25.0.50; (ad-is-adviced sym) is inconsistent with (advice--p (advice--symbol-function sym))

[Stefan Monnier]

> `ad-is-advised' expands to:
>     (get 'foo 'ad-advice-info)
> This code will not detect if the function `foo' is being instrumented
> with `elp-instrument-package' (which is a form of advice).

That's because ad-is-advised tells you "is there a "defadvice" on this
function" rather than "is there some kind of advice-like thingy on this
function".
Since this is used by advice.el internally, changing it might just break
advice.el.


        Stefan