LayoutTest fast/dom/Window/window-resize-contents.html is a flaky timeout https://build.webkit.org/results/Apple%20El%20Capitan%20Debug%20WK2%20(Tests)/r209216%20(9697)/results.html http://webkit-test-results.webkit.org/dashboards/flakiness_dashboard.html#showAllRuns=true&tests=fast%2Fdom%2FWindow%2Fwindow-resize-contents.html
This is not a recent regression, this test has been flaky for a while. Marked as such in https://trac.webkit.org/changeset/209290