Various JSHint fixes. see #26446.


git-svn-id: https://develop.svn.wordpress.org/trunk@27131 602fd350-edb4-49c9-b593-d223f7449a82
Improve parameter documentation of add_meta_box().

props philiparthurmoore, DrewAPicture.
fixes #26698.


git-svn-id: https://develop.svn.wordpress.org/trunk@27132 602fd350-edb4-49c9-b593-d223f7449a82