LayoutTest mathml/opentype/large-operators-displaystyle-dynamic.html is a flaky failure https://build.webkit.org/results/Apple%20Sierra%20Release%20WK2%20(Tests)/r210927%20(2828)/results.html https://webkit-test-results.webkit.org/dashboards/flakiness_dashboard.html#showAllRuns=true&tests=mathml%2Fopentype%2Flarge-operators-displaystyle-dynamic.html
For macOS, this seems to be limited to Sierra Release WK2
Marked test as flaky in http://trac.webkit.org/projects/webkit/changeset/211843