The code in question is:

            } catch (Exception e) {
                if (!((_ok) ? true : (Math.random() > 0.1))) {
                    return res;
                }
                (error logging)
                _ok = false;
            }

A 10% percent chance to skip logging under certain circumstances. Very strange code, and a strange way to write it. Also wouldn't this be equivalent to

    if (!_ok || (Math.random() > 0.1))