Make the value nil in text-quoting-style mean what it does in Emacs 25.

This is a partial reversion of yesterday's commit by the same author, which
changed the meaning of nil and introduced the new value t.

* src/doc.c (text_quoting_style, text-quoting-style)
(internal--text-quoting-flag): Revert yesterday's changes.

* lisp/cus-start.el: (top level): Amend the entry for text-quoting-style.

* etc/NEWS: Amend the entry for text-quoting-style.

* doc/lispref/control.texi (Signalling Errors)
* doc/lispref/display.texi (Displaying Messages)
* doc/lispref/strings.texi (Formatting Strings): Bind text-quoting-style to
grave rather than nil to inhibit translation of quotes.

* doc/lispref/help.texi (Keys in Documentation): Revert the description of the
proposed new default, t.

1 files changed, 4 insertions, 4 deletions

diff --git a/doc/lispref/strings.texi b/doc/lispref/strings.texi
index 117a373a190..10385e05501 100644
--- a/doc/lispref/strings.texi
+++ b/doc/lispref/strings.texi
@@ -836,10 +836,10 @@ this'} typically generates curved quotes @t{‘like this’}.  In
 contrast, a format that quotes with only apostrophes @t{'like this'}
 typically generates two closing curved quotes @t{’like this’}, an
 unusual style in English.  One way around such problems is to bind
-@code{text-quoting-style} to @code{nil} around calls to
-@code{format-message}; this causes the @acronym{ASCII} quoting
-characters to be output unchanged.  @xref{Keys in Documentation}, for
-how the @code{text-quoting-style} variable affects generated quotes.
+@code{text-quoting-style} to the symbol @code{grave} around calls to
+@code{format-message}; this causes @acronym{ASCII} quoting characters
+to be output unchanged.  @xref{Keys in Documentation}, for how the
+@code{text-quoting-style} variable affects generated quotes.
 @end defun
 
 @cindex @samp{%} in format