fix type error

src/fd_ws.erl

@@ -148,9 +148,9 @@ handshake2(#request{headers = DowncaseHeaders}) ->
     % sec-websocket-version: 13         % must be EXACTLY 13
     % connection:            Upgrade    % must include the token "Upgrade"
     % upgrade:               websocket  % must include the token "websocket"
-    MapHeaders         = maps:from_list(DowncaseHeaders),
-    ClientProtocols    = client_protocols(MapHeaders),
+    ClientProtocols    = client_protocols(DowncaseHeaders),
     ClientExtensions   = client_extensions(DowncaseHeaders),
+    MapHeaders         = maps:from_list(DowncaseHeaders),
     MaybeResponseToken = validate_headers(MapHeaders),
     case MaybeResponseToken of
         {ok, ResponseToken} ->
@@ -754,9 +754,10 @@ send_frame(Sock, Frame) ->
 % @private
 % render a frame
 %
+% RSV is always <<0:3>> in rendered frame
+%
 % TODO: this doesn't check/do masking
 %
-% also RSV is always <<0:3>> in rendered frame
 %
 % This is a non-issue as long as this is only used for rendering messages sent
 % from server to client (unmasked per protocol). However, for debugging