Revert "Update for Go's new http.Request.Header type."

This reverts commit b021345ed6.

lib/go/httprange/range.go

@@ -46,8 +46,8 @@ var WholeRange = &Range{0, -1}
 var rangePattern = regexp.MustCompile(`bytes=([0-9]+)-([0-9]*)`)
 
 func FromRequest(req *http.Request) *Range {
-	rrange := req.Header.Get("Range")
-	if rrange == "" {
+	rrange, ok := req.Header["Range"]
+	if !ok {
 		return WholeRange
 	}
 	return FromString(rrange)

server/go/auth/auth.go

@@ -29,8 +29,8 @@ var kBasicAuthPattern *regexp.Regexp = regexp.MustCompile(`^Basic ([a-zA-Z0-9\+/
 var AccessPassword string
 
 func IsAuthorized(req *http.Request) bool {
-	auth := req.Header.Get("Authorization")
-	if auth == "" {
+	auth, present := req.Header["Authorization"]
+	if !present {
 		return false
 	}
 	matches := kBasicAuthPattern.FindStringSubmatch(auth)

website/cgi.go

@@ -69,15 +69,15 @@ func (h *CgiHandler) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
 		"SERVER_PORT=" + port,
 	}
 
-	for k, _ := range req.Header {
+	for k, v := range req.Header {
 		k = strings.Map(upperCaseAndUnderscore, k)
-		env = append(env, "HTTP_"+k+"="+req.Header.Get(k))
+		env = append(env, "HTTP_"+k+"="+v)
 	}
 
 	if req.ContentLength > 0 {
 		env = append(env, fmt.Sprintf("CONTENT_LENGTH=%d", req.ContentLength))
 	}
-	if ctype := req.Header.Get("Content-Type"); ctype != "" {
+	if ctype, ok := req.Header["Content-Type"]; ok {
 		env = append(env, "CONTENT_TYPE="+ctype)
 	}