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

[Carsten Bormann]

Killing an nXML buffer sometimes leads to a repeated occurrence of the error:

Error in timer: (error "Selecting deleted buffer")

More detail:

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])

I don't have a detailed procedure for reproducing this, yet.

At least, rng-validate-while-idle should kill the timer if the buffer
has been killed.

In GNU Emacs 24.3.50.1 (x86_64-apple-darwin, NS apple-appkit-1038.36)
 of 2013-03-17 on bob.porkrind.org
Bzr revision: 112062 jay.p.belanger@gmail.com-20130317001909-prx18039wq0qmiv4
Windowing system distributor `Apple', version 10.3.1187
Configured using:
 `configure --host=x86_64-apple-darwin --build=i686-apple-darwin
 --with-ns'