[Modify] Replace it

websocket-sharp/HttpResponse.cs

@@ -104,11 +104,9 @@ namespace WebSocketSharp
 
     public bool IsWebSocketResponse {
       get {
-        var headers = Headers;
+        return ProtocolVersion > HttpVersion.Version10
-        return ProtocolVersion > HttpVersion.Version10 &&
+               && _code == "101"
-               _code == "101" &&
+               && Headers.Upgrades ("websocket");
-               headers.Contains ("Upgrade", "websocket") &&
-               headers.Contains ("Connection", "Upgrade");
       }
     }