Re: "Final" version of tty child frames

[martin rudalics]

>> LGTM, please apply.
>
> Now installed on the master branch, thanks.

This was supposedly posted in the wrong sub-thread.

It gives me here

../../src/term.c: In function ‘tty_frame_at’:
../../src/term.c:2600:68: error: invalid operands to binary != (have 
‘Lisp_Object’ and ‘Lisp_Object’)
 2600 |   for (Lisp_Object frames = Ftty_frame_list_z_order (Qnil); frames != 
Qnil;
      |                                                                    ^~

And while we're here please avoid idioms like

  if (! FRAMEP (last_mouse_frame))
    return;

  *fp = XFRAME (last_mouse_frame);

since we just had a quite similar bug elsewhere.  As a rule, always
write

  if (!FRAMEP (last_mouse_frame)
      || !FRAME_LIVE_P (XFRAME (last_mouse_frame)))
    return;

Thanks, martin