Warning when array passed to wp_check_invalid_utf8()

[leedxw]

wp_check_invalid_utf8() specifies

 * @param string $text   The text which is to be checked.

and will trigger the following warning if passed an array.

PHP Warning:  Array to string conversion in /var/www/html/wp-includes/formatting.php on line 1096

To reproduce

curl -v "http://localhost/wp-login.php?redirect_to[]=http://"

I would suggest returning an empty string if presented with an array.

[leedxw]

Modify wp_check_invalid_utf8() to return an empty string if passed an array

[garrigan]

Sharing: ​https://wordpress.org/support/topic/post-wp-admin-admin-ajax-php-http-2-0-404/#post-18357101