LayoutTest fast/events/before-unload-returnValue.html is a flaky failure (reporting FailureNotTested) https://build.webkit.org/results/Apple%20Sierra%20Debug%20WK2%20(Tests)/r217272%20(1154)/results.html https://webkit-test-results.webkit.org/dashboards/flakiness_dashboard.html#tests=fast%2Fevents%2Fbefore-unload-returnValue.html
*** This bug has been marked as a duplicate of bug 172672 ***