anchor.diff:  -spec route_message(Msg :: #client_message{} | #server_message{}) ->
       ok | {ok, #server_message{}} | {error, term()}.
   route_message(Msg) ->
  -    route_message(Msg, undefined, undefined).
  +    route_message(Msg, undefined, undefined, false).
   
   %%--------------------------------------------------------------------
   %% @doc
  
positive.code: -include_lib("cluster_worker/include/exometer_utils.hrl").
  
  %% API
  -export([preroute_message/4, route_message/1, route_message/3,
      route_proxy_message/2]).
  -export([effective_session_id/1]).
  
  
negative.code:     SessId, _Sock, _Transport) ->
      sequencer:route_message(Msg, SessId);
  preroute_message(#client_message{message_stream = undefined} = Msg,
      SessId, Sock, Transport) ->
      IsProviderSession = session_manager:is_provider_session_id(SessId),
      router:route_message(Msg, Sock, Transport, IsProviderSession);
  preroute_message(#client_message{message_body = #subscription{}} = Msg,
      SessId, _Sock, _Transport) ->
      case session_manager:is_provider_session_id(SessId) of
  