Bizarre behavior when throw exceptions without try in a continuation block about continuation HOT 1 OPEN

function (_$cont) {
  var _$has_catched = false;
  try {
    test(function (arguments, _$param0, _$param1) {
      try {
        _$err = _$param0;
        a = _$param1;
        if (_$err)
          throw _$err;
        _$cont();
      } catch (_$err) {
        if (_$has_catched)
          throw _$err;
        _$has_catched = true;
        _$cont(_$err);
      }
    }.bind(this, arguments));
  } catch (_$err) {
    if (_$has_catched)
      throw _$err;
    _$has_catched = true;
    _$cont(_$err);
  }
}