Fix JSHint errors in customize-controls.js.

props jorbin.
fixes #25917.

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git-svn-id: http://core.svn.wordpress.org/trunk@26114 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Fix JSHint errors in two files. see #25957, #25864. (Similar names but separate files.)

Built from https://develop.svn.wordpress.org/trunk@26207


git-svn-id: http://core.svn.wordpress.org/trunk@26115 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Residual JSHint fixes in common.js and edit-comments.js.

see #25912, #25979.

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git-svn-id: http://core.svn.wordpress.org/trunk@26116 1a063a9b-81f0-0310-95a4-ce76da25c4cd
JSHint fixes for word-count.js and wp-mediaelement.js. see #25187.

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git-svn-id: http://core.svn.wordpress.org/trunk@26117 1a063a9b-81f0-0310-95a4-ce76da25c4cd