Allow has_post_format() to be used to check for any format.

Calling has_post_format() with an empty list of $format will check if the
provided post has any associated format at all.

Props obenland, DrewAPicture, nacin. Fixes #24906.

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git-svn-id: http://core.svn.wordpress.org/trunk@26251 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Fourteen: avoid Featured Content thumbnail overflow, props binarymoon. Fixes #26190.

Built from https://develop.svn.wordpress.org/trunk@26351


git-svn-id: http://core.svn.wordpress.org/trunk@26252 1a063a9b-81f0-0310-95a4-ce76da25c4cd