bug#17439: 24.3.50; run-with-idle-timer runs on focus-out

[Eli Zaretskii <eliz@gnu.org>]

> From: Juri Linkov <juri@jurta.org>
> Date: Thu, 08 May 2014 23:45:27 +0300
> 
> Some change a few months ago introduced a significant inconvenience.
> After switching to another application, the focus returns back to Emacs.
> It happens when using `mouse-avoidance-mode' customized to `banish'.
> This mode relies on `run-with-idle-timer' that moves the mouse cursor
> on a new input.  This caused no problems in prior releases.
> 
> However, now input events include a new event type `focus-out',
> so the mouse cursor is moved on switching from Emacs frame
> (and the new mouse cursor position puts the focus back
> due to specific configuration).
> 
> This code illustrates the problem:
> 
> (defun test () (message "%S" last-input-event))
> (setq timer (run-with-idle-timer 0.1 t 'test))
> 
> On switching out it prints to *Messages*:
> 
> (focus-in #<frame emacs@localhost 0x1121908>)
> (focus-out #<frame emacs@localhost 0x1121908>)
> 
> This specific problem can be fixed by this patch:

Why did you add focus-in as well?  Wouldn't you want the mouse moved
when you are about to type?