Docs: Misc corrections and additions to inline documentation.

See #39130
Props keesiemeijer

Built from https://develop.svn.wordpress.org/trunk@39639


git-svn-id: http://core.svn.wordpress.org/trunk@39579 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/rest-api/endpoints/class-wp-rest-settings-controller.php

@@ -306,6 +306,7 @@ class WP_REST_Settings_Controller extends WP_REST_Controller {
 	 * provide a wrapper sanitizer to whitelist the use of `null`.
 	 *
 	 * @since 4.7.0
+	 * @access public
 	 *
 	 * @param  mixed           $value   The value for the setting.
 	 * @param  WP_REST_Request $request The request object.