Upgrading server package dependencies (#12559)

vendor/github.com/gorilla/handlers/README.md

@@ -1,6 +1,7 @@
 gorilla/handlers
 ================
-[![GoDoc](https://godoc.org/github.com/gorilla/handlers?status.svg)](https://godoc.org/github.com/gorilla/handlers) [![Build Status](https://travis-ci.org/gorilla/handlers.svg?branch=master)](https://travis-ci.org/gorilla/handlers)
+[![GoDoc](https://godoc.org/github.com/gorilla/handlers?status.svg)](https://godoc.org/github.com/gorilla/handlers)
+[![CircleCI](https://circleci.com/gh/gorilla/handlers.svg?style=svg)](https://circleci.com/gh/gorilla/handlers)
 [![Sourcegraph](https://sourcegraph.com/github.com/gorilla/handlers/-/badge.svg)](https://sourcegraph.com/github.com/gorilla/handlers?badge)
 
 

vendor/github.com/gorilla/handlers/compress.go

@@ -80,6 +80,7 @@ func CompressHandlerLevel(h http.Handler, level int) http.Handler {
 			switch strings.TrimSpace(enc) {
 			case "gzip":
 				w.Header().Set("Content-Encoding", "gzip")
+				r.Header.Del("Accept-Encoding")
 				w.Header().Add("Vary", "Accept-Encoding")
 
 				gw, _ := gzip.NewWriterLevel(w, level)
@@ -111,6 +112,7 @@ func CompressHandlerLevel(h http.Handler, level int) http.Handler {
 				break L
 			case "deflate":
 				w.Header().Set("Content-Encoding", "deflate")
+				r.Header.Del("Accept-Encoding")
 				w.Header().Add("Vary", "Accept-Encoding")
 
 				fw, _ := flate.NewWriter(w, level)

vendor/github.com/gorilla/handlers/logging.go

@@ -43,6 +43,9 @@ func (h loggingHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 	url := *req.URL
 
 	h.handler.ServeHTTP(logger, req)
+	if req.MultipartForm != nil {
+		req.MultipartForm.RemoveAll()
+	}
 
 	params := LogFormatterParams{
 		Request:    req,

vendor/github.com/gorilla/handlers/proxy_headers.go

@@ -31,8 +31,8 @@ var (
 // ProxyHeaders inspects common reverse proxy headers and sets the corresponding
 // fields in the HTTP request struct. These are X-Forwarded-For and X-Real-IP
 // for the remote (client) IP address, X-Forwarded-Proto or X-Forwarded-Scheme
-// for the scheme (http|https) and the RFC7239 Forwarded header, which may
-// include both client IPs and schemes.
+// for the scheme (http|https), X-Forwarded-Host for the host and the RFC7239
+// Forwarded header, which may include both client IPs and schemes.
 //
 // NOTE: This middleware should only be used when behind a reverse
 // proxy like nginx, HAProxy or Apache. Reverse proxies that don't (or are