message: fix boost bind usafe capture of this as well
diff: @@ -924,14 +924,30 @@ namespace eosio {
  void connection::sync_wait( ) {
  response_expected->expires_from_now( my_impl->resp_expected_period);
  - response_expected->async_wait( boost::bind(&connection::sync_timeout,
  - this, boost::asio::placeholders::error));
  + connection_wptr c(shared_from_this());
  + response_expected->async_wait( [c]( boost::system::error_code ec){
  + connection_ptr conn = c.lock();
  + if (!conn) {
  + // connection was destroyed before this lambda was delivered
  + return;
  + }
  +
  + conn->sync_timeout(ec);
  + } );
  }
  void connection::fetch_wait( ) {
  response_expected->expires_from_now( my_impl->resp_expected_period);
  - response_expected->async_wait( boost::bind(&connection::fetch_timeout,
  - this, boost::asio::placeholders::error));
  + connection_wptr c(shared_from_this());
  + response_expected->async_wait( [c]( boost::system::error_code ec){
  + connection_ptr conn = c.lock();
  + if (!conn) {
  + // connection was destroyed before this lambda was delivered
  + return;
  + }
  +
  + conn->fetch_timeout(ec);
  + } );
  }
  void connection::sync_timeout( boost::system::error_code ec ) {
  