bug#10224: 24.0.92; M-w inhibits echoing of prefix arguments

[Stephen Berman]

1. emacs -Q
2. Type `C-u' => in the echo area you see "C-u-"
3. Set the mark (e.g. by typing `C-SPC') and then type `M-w'.
4. Type `C-u' => in the echo area you see nothing, for this and
subsequent prefix arguments.  `M-x' is, however, echoed.

The above recipe did not work in my previous build from 2011-12-03,
which may implicate this change:

2011-12-05  Chong Yidong  <cyd@gnu.org>

        * keyboard.c (process_special_events): New function.
        (swallow_events, Finput_pending_p): Use it (Bug#10195).

However, in my build from 2011-12-03, if I disabled transient-mark-mode
before step 3 above, then `M-w' has the same inhibiting effect on prefix
arguments, so if the above change is involved, then only to expose the
bug in transient-mark-mode.  Yet this is a recent bug, since I did not
observe it in builds prior to 2011-12-03.


In GNU Emacs 24.0.92.2 (i686-suse-linux-gnu, GTK+ Version 2.24.7)
 of 2011-12-05 on escher
Windowing system distributor `The X.Org Foundation', version 11.0.11004000
configured using `configure  '--without-toolkit-scroll-bars' 'CFLAGS=-g''

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: en_US.UTF-8
  value of $XMODIFIERS: @im=local
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t