Twenty Eleven: make sure top post meta output isn't broken on small screens. Fixes #27061.

git-svn-id: https://develop.svn.wordpress.org/trunk@27570 602fd350-edb4-49c9-b593-d223f7449a82
Twenty Twelve: remove unused `singular` selectors in print CSS block. Props jbkkd, fixes #26866.

git-svn-id: https://develop.svn.wordpress.org/trunk@27571 602fd350-edb4-49c9-b593-d223f7449a82
Twenty Twelve: style `select` element. Props ramonchiara, fixes #27434.

git-svn-id: https://develop.svn.wordpress.org/trunk@27572 602fd350-edb4-49c9-b593-d223f7449a82