Fix JSHint errors in nav-menu.js.

props atimmer.
fixes #25953.

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git-svn-id: http://core.svn.wordpress.org/trunk@26074 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Bacground Updates: Move the 'automatic_updates_complete' hook to only fire when some updates have actually been completed. Props nacin. Fixes #25841

Built from https://develop.svn.wordpress.org/trunk@26164


git-svn-id: http://core.svn.wordpress.org/trunk@26075 1a063a9b-81f0-0310-95a4-ce76da25c4cd