[php-src] Issue #8206: filenames in multipart/form-data are not percent decoded

Issue: https://github.com/php/php-src/issues/8206 Comment Author: cmb69 Well, the [WHATWG living "standard" currently claims](https://html.spec.whatwg.org/multipage/form-control-infrastructure.html#multipart-form-data): > For field names and filenames for file fields, the result of the encoding in the previous > bullet point must be escaped by replacing any 0x0A (LF) bytes with the byte sequence > %0A, 0x0D (CR) with %0D and 0x22 > (") with %22. The user agent must not perform any other > escapes. So these browsers appear to behave according to that standard (although that standardized behavior makes no sense).