bug#16761: 24.3.50; focus-in-hook not running accurately when frame switches to terminal

[Steven Edwards <cureadvocate@gmail.com>]

> You don't say what you expect to happen.  Do you expect a focus-in and
> focus-out event to be generated for terminal frames?  Or do you expect
> (or need) something else?

I need a focus-in event to occur when switching to a terminal frame;
the code I provided was simply to demonstrate and focus on the error.

The real code:

---
(defun rand/swap-theme (from to)
  (disable-theme from)
  (enable-theme to))

(defun rand/choose-theme ()
  (cond
    ((memq window-system '(x w32 ns)) (rand/swap-theme 'Custom 'assemblage))
    (t (rand/swap-theme 'assemblage 'Custom))))

(add-hook 'focus-in-hook 'rand/choose-theme)
---

The goal is to switch to a terminal-friendly theme when I'm in tmux
and a GUI friendly theme when I'm in a graphical environment.  The
problem seems to be that the hooks in focus-in-hooks aren't being
executed when I switch to a terminal frame.

Best,

Steven