Ensure that draft posts cannot be given a non-unique post slug when using Quick Edit.

fixes #22902. props SergeyBiryukov.

git-svn-id: http://core.svn.wordpress.org/trunk@24206 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Use ellipsis instead of three dots. props tjsingleton, jordie23, wojtek.szkutnik, DrewAPicture, SergeyBiryukov. see #8714.

git-svn-id: http://core.svn.wordpress.org/trunk@24207 1a063a9b-81f0-0310-95a4-ce76da25c4cd