cmd/godoc: fix app engine version

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/5902060

src/cmd/godoc/appinit.go

@@ -19,7 +19,7 @@ import (
 func serveError(w http.ResponseWriter, r *http.Request, relpath string, err error) {
 	contents := applyTemplate(errorHTML, "errorHTML", err) // err may contain an absolute path!
 	w.WriteHeader(http.StatusNotFound)
-	servePage(w, "File "+relpath, "", "", contents)
+	servePage(w, relpath, "File "+relpath, "", "", contents)
 }
 
 func init() {