websocket: fix a minor grammar issue in a comment.

Fixes golang/go#10881

Change-Id: I9f16dd0425d4e3c4a05530411eb29a7193a9d242
Reviewed-on: https://go-review.googlesource.com/10621
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Author: nigeltao

websocket/server.go

@@ -95,8 +95,8 @@ func (s Server) serveWebSocket(w http.ResponseWriter, req *http.Request) {
 // You might want to verify websocket.Conn.Config().Origin in the func.
 // If you use Server instead of Handler, you could call websocket.Origin and
 // check the origin in your Handshake func. So, if you want to accept
-// non-browser client, which doesn't send Origin header, you could use Server
-//. that doesn't check origin in its Handshake.
+// non-browser clients, which do not send an Origin header, set a
+// Server.Handshake that does not check the origin.
 type Handler func(*Conn)
 
 func checkOrigin(config *Config, req *http.Request) (err error) {