Stop signaling an error when reading "smart quotes" in symbols

Revert commits from 2018-01-28 "Fix round tripping of read->print for
symbols with strange quotes", and 2017-07-22 "Signal error for symbol
names with strange quotes (Bug#2967)".
* etc/NEWS: Remove corresponding entries.
* src/character.c (confusable_symbol_character_p):
* test/src/lread-tests.el (lread-tests--old-style-backquotes): Remove.
* src/lread.c (read1): Don't signal error on confusable character.
* src/print.c (print_object): Don't escape confusable characters.

1 files changed, 0 insertions, 9 deletions

diff --git a/etc/NEWS b/etc/NEWS
index cb73e46358a..3a2efcfc2e0 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -2972,15 +2972,6 @@ and if the new behavior breaks your code please email
 <32252@debbugs.gnu.org>.  Because '%o' and '%x' can now format signed
 integers, they now support the '+' and space flags.
 
-** To avoid confusion caused by "smart quotes", the reader signals an
-error when reading Lisp symbols which begin with one of the following
-quotation characters: ‘’‛“”‟〞＂＇.  A symbol beginning with such a
-character can be written by escaping the quotation character with a
-backslash.  For example:
-
-    (read "‘smart") => (invalid-read-syntax "strange quote" "‘")
-    (read "\\‘smart") == (intern "‘smart")
-
 +++
 ** Omitting variables after '&optional' and '&rest' is now allowed.
 For example '(defun foo (&optional))' is no longer an error.  This is