Twenty Fifteen: layout correction for IE8 and IE7 after r30388 introduced a defect with the header there.

Props iamtakashi, fixes #30630.



git-svn-id: https://develop.svn.wordpress.org/trunk@30789 602fd350-edb4-49c9-b593-d223f7449a82
Twenty Fifteen: moving to a single line for tranlator comments to prevent them being missed in i18n tools.

Props netweb, DrewAPicture, fixes #30603.



git-svn-id: https://develop.svn.wordpress.org/trunk@30790 602fd350-edb4-49c9-b593-d223f7449a82