Rename some variables for consistency. Remove redundant absint() call. see #24010.

git-svn-id: http://core.svn.wordpress.org/trunk@24024 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Revisions: when upgrading the revision author don't add a copy of the post as latest revision when some of the revisions are already at v1. See #16215

git-svn-id: http://core.svn.wordpress.org/trunk@24025 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Revisions: look at the version of the earliest revision when checking whether to upgrade the revisions authors, see #16215

git-svn-id: http://core.svn.wordpress.org/trunk@24026 1a063a9b-81f0-0310-95a4-ce76da25c4cd