anchor.diff:      inc_counter(non_native_vbucket_filter_changes),
       (catch master_activity_events:note_vbucket_filter_change_old()),
   
  -    ok = gen_server:call(UpstreamSender, silence_upstream),
  +    erlang:unlink(UpstreamSender),
  +    exit(UpstreamSender, shutdown),
       ok = gen_tcp:close(Upstream),
       ?log_debug("Closed upstream connection"),
   
  
positive.code: 
  complete_native_vb_filter_change(#state{downstream=Downstream,
                                          upstream=Upstream,
                                          upstream_sender=UpstreamSender,
                                          vb_filter_change_state=ChangeState,
                                          vb_filter_change_owner=Owner} = State) ->
      completed = ChangeState,
  
negative.code: -export([init/1, handle_call/3, handle_cast/2,
           handle_info/2, terminate/2, code_change/3]).
  
  -type vb_filter_change_state() :: not_started | started | half_completed | completed.
  
  -record(had_backfill, {value :: boolean() | undefined,
                         backfill_opaque :: undefined | non_neg_integer(),
  