Add Rdio to the default oembed providers list.

Props zekeweeks
fixes #24242


git-svn-id: https://core.svn.wordpress.org/trunk@24160 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Respect the link to setting when inserting a gallery.

Props SergeyBiryukov
fixes #23298


git-svn-id: https://core.svn.wordpress.org/trunk@24161 1a063a9b-81f0-0310-95a4-ce76da25c4cd