Update the Scribd oEmbed pattern to more actually represent which endpoints from the site are discoverable.

See #28379.

Built from https://develop.svn.wordpress.org/trunk@28595


git-svn-id: http://core.svn.wordpress.org/trunk@28420 1a063a9b-81f0-0310-95a4-ce76da25c4cd
RIP Viddler oEmbed support.

More: https://gigaom.com/2014/02/07/viddler-gets-ready-to-delete-personal-videos/

See #28379.


Built from https://develop.svn.wordpress.org/trunk@28596


git-svn-id: http://core.svn.wordpress.org/trunk@28421 1a063a9b-81f0-0310-95a4-ce76da25c4cd