Subject: 24.3; Emacs cannot visit a file named " "

From: Ulrich Mueller <[email-masked]>
Date: Thu, 22 Aug 2013 17:58:31 +0200

$ emacs -Q " "

outputs a message "Empty string for buffer name is not allowed" and
refuses to visit the file.

This still worked in Emacs 22.3. Seems that this commit broke it:
http://bzr.savannah.gnu.org/lh/emacs/trunk/revision/79740