Synchronize the documentation between two places, use `WP_Customize_Control::__construct()` as the canonical source. Props hAmpzter, marekdedic, SergeyBiryukov. Fixes #48343. Built from https://develop.svn.wordpress.org/trunk@47364 git-svn-id: http://core.svn.wordpress.org/trunk@47151 1a063a9b-81f0-0310-95a4-ce76da25c4cd