Restore CSS for the Site Content, née Right Now, Dashboard widget. Removes a nice large swath of unnecessary styles. fixes #26392, see #25824.

Built from https://develop.svn.wordpress.org/trunk@26656


git-svn-id: http://core.svn.wordpress.org/trunk@26546 1a063a9b-81f0-0310-95a4-ce76da25c4cd