[PATCH 2/3] Add a frame_changed observer

[Tom Tromey]

>>>>> "Maxime" == Maxime Coste <frrrwww@gmail.com> writes:

Maxime> +@deftypefun void frame_changed (struct frame_info *@var{frame})
Maxime> +the selected frame has changed;
Maxime> +@end deftypefun

I think this needs more text and should probably be a full sentence.
Like

    The selected frame has changed in a user-visible way.  @var{frame}
    is the new frame.

Tom