Remove unnecessary label, placeholder, and class for a hidden input. see #23938.


git-svn-id: http://core.svn.wordpress.org/trunk@23931 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Merge commit 'bd4cc15d68b0ba134a1fbda2e78dca08b4ad3afc'