bug#24931: 25.1.50; recentf breaks M-x tetris scoring

[Robert Marshall <robert@capuchin.co.uk>]

With emacs -Q
evaluate
(require 'recentf)
(recentf-mode t)

and then M-x tetris

just let the blocks pile up to finish quickly, when it completes I
get the message

   File exists, but cannot be read

when it tries to access the score file and no score gets added - if it
was going to do so. Without those recentf lines the score file is read
successfully.

The issue doesn't appear to be dependent upon
~/.emacs.d/games/tetris-scores in the recentf list

Robert

In GNU Emacs 25.1.50.6 (x86_64-unknown-linux-gnu, GTK+ Version 3.18.9)
 of 2016-09-03 built on robert-new-desktop
Repository revision: 2ad16e4bf9b43c169bcfa1e6240584488fbc3d78
Windowing system distributor 'The X.Org Foundation', version 11.0.11804000
System Description:	Ubuntu 16.04.1 LTS


Configured features:
XPM JPEG TIFF GIF PNG SOUND DBUS GSETTINGS NOTIFY GNUTLS LIBXML2
FREETYPE XFT ZLIB TOOLKIT_SCROLL_BARS GTK3 X11

Important settings:
  value of $LANG: en_GB.UTF-8
  locale-coding-system: utf-8-unix

Major mode: Group

Minor modes in effect:
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  hi-lock-mode: t
  desktop-save-mode: t
  shell-dirtrack-mode: t
  recentf-mode: t
  show-paren-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  buffer-read-only: t
  line-number-mode: t
  transient-mark-mode: t

Load-path shadows:
None found.

Features:
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Memory information:
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