Fix issue where post locks were not updating on autosaves. props benbalter,...

Fix issue where post locks were not updating on autosaves. props benbalter, fixes #18642. see #18515 for more on locking. broken in [12991], see #11889.

git-svn-id: https://core.svn.wordpress.org/trunk@18709 1a063a9b-81f0-0310-95a4-ce76da25c4cd