bug#21305: 25.0.50; `get-buffer-window-list' doc - what order?

[Drew Adams]

BTW, it would be nice to know whether `get-buffer-window-list'
returns a new list or returns a list that is pointed to (used)
by something else.

In particular, it would be good to know whether one can use
`sort' on it (e.g., `sort' according to `window-use-time')
without bothering something else somewhere.  I'm supposing so.