Add 'status-sticky' class in get_post_class() for sticky posts in the admin.

props mordauk, netweb.
fixes #22590.
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git-svn-id: http://core.svn.wordpress.org/trunk@28791 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Remove debug remnants, see #28595
Built from https://develop.svn.wordpress.org/trunk@29004


git-svn-id: http://core.svn.wordpress.org/trunk@28792 1a063a9b-81f0-0310-95a4-ce76da25c4cd