Nav menus: Allow assigning a new menu to an existing location when no theme setting is currently saved.

Merges [25195] to the 3.6 branch.

props ocean90.
fixes #25064.


git-svn-id: https://develop.svn.wordpress.org/branches/3.6@25232 602fd350-edb4-49c9-b593-d223f7449a82
Remove display of 'Previously restored by' in the revisions meta box as it is busted.

Fixes invalid markup (missing closing ul tag) when there was no previously restored revision.

Merges [25194] to the 3.6 branch.
fixes #25051.



git-svn-id: https://develop.svn.wordpress.org/branches/3.6@25233 602fd350-edb4-49c9-b593-d223f7449a82