bug#13999: 24.3.50; rng-validate-while-idle -> (error "Selecting deleted buffer")

[Stefan Monnier]

> Debugger entered--Lisp error: (error "Selecting deleted buffer")
>   rng-validate-while-idle(#<killed buffer>)
>   apply(rng-validate-while-idle #<killed buffer>)
>   byte-code("r\301\302H\303H\"\210)\301\207" [timer apply 5 6] 4)
>   timer-event-handler([t 0 1 500000 t rng-validate-while-idle (#<killed 
> buffer>) idle 0])

Right, rng-validate-while-idle needs to check that its buffer is
still live.  Ideally it should also disable the corresponding timer if
the buffer died.
Could someone take care of it?


        Stefan