Replace use of obsolete variable `last-command-char` by @maser [fix GH-290]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@40401 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

misc/ruby-mode.el

@@ -874,7 +874,7 @@ Also ignores spaces after parenthesis when 'space."
 
 (defun ruby-electric-brace (arg)
   (interactive "P")
-  (insert-char last-command-char 1)
+  (insert-char last-command-event 1)
   (ruby-indent-line t)
   (delete-char -1)
   (self-insert-command (prefix-numeric-value arg)))