bug#24618: 26.0.50; `condition-case' doesn't allow catching all signals

[Philipp Stephani]

Consider the following code:

(condition-case err
    (signal 'does-not-exist '(1 2))
  (error (print err)))

The signal is not caught by condition-case because it has no error
conditions.  This makes it impossible to reliably catch all signals
(without abusing the debugger).  I propose that an error condition of
't' in `condition-case' should be interpreted as 'all conditions'.


In GNU Emacs 26.0.50.1 (x86_64-unknown-linux-gnu, GTK+ Version 3.10.8)
 of 2016-10-04 built on unknown
Repository revision: e2913dc880b9843bf69cf885270551bafeb46120
Windowing system distributor 'The X.Org Foundation', version 11.0.11501000
System Description:     Ubuntu 14.04 LTS

Recent messages:
mwheel-scroll: Beginning of buffer [7 times]
Mark set
Sending...
Mark set [2 times]
Sending via mail...
Setting ‘smtpmail-smtp-server’ temporarily since "emacs -q" would overwrite 
customizations
Setting ‘smtpmail-smtp-service’ temporarily since "emacs -q" would overwrite 
customizations
Sending email 
Sending email done
Sending...done

Configured using:
 'configure --with-modules --enable-checking
 --enable-check-lisp-object-type'

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

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

Major mode: Lisp Interaction

Minor modes in effect:
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  electric-indent-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
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  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
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  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Load-path shadows:
None found.

Features:
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seq byte-opt gv bytecomp byte-compile cl-extra help-mode cconv
cl-loaddefs pcase cl-lib dired dired-loaddefs format-spec rfc822 mml
easymenu mml-sec password-cache epa derived epg epg-config gnus-util
rmail rmail-loaddefs mm-decode mm-bodies mm-encode mail-parse rfc2231
mailabbrev gmm-utils mailheader sendmail rfc2047 rfc2045 ietf-drums
mm-util mail-prsvr mail-utils time-date mule-util tooltip eldoc electric
uniquify ediff-hook vc-hooks lisp-float-type mwheel term/x-win x-win
term/common-win x-dnd tool-bar dnd fontset image regexp-opt fringe
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syntax facemenu font-core term/tty-colors frame cl-generic cham georgian
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hashtable-print-readable backquote inotify dynamic-setting
system-font-setting font-render-setting move-toolbar gtk x-toolkit x
multi-tty make-network-process emacs)

Memory information:
((conses 16 126071 14602)
 (symbols 48 22713 6)
 (miscs 40 341 241)
 (strings 32 23705 8690)
 (string-bytes 1 748309)
 (vectors 16 22599)
 (vector-slots 8 1236864 203799)
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 (intervals 56 534 27)
 (buffers 976 15)
 (heap 1024 59649 5444))

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