webkit_layout_tests failing on 2 builders

Builders failed on: 
- WebKit Linux Trusty: 
  https://build.chromium.org/p/chromium.webkit/builders/WebKit%20Linux%20Trusty
- WebKit Linux Trusty Leak: 
  https://build.chromium.org/p/chromium.webkit/builders/WebKit%20Linux%20Trusty%20Leak

external/wpt/html/semantics/tabular-data/processing-model-1/span-limits.html [1] is failing after [2]

- [1]: https://test-results.appspot.com/dashboards/flakiness_dashboard.html#tests=external%2Fwpt%2Fhtml%2Fsemantics%2Ftabular-data%2Fprocessing-model-1%2Fspan-limits.html&testType=webkit_layout_tests
- [2]: https://chromium.googlesource.com/chromium/src/+/dfc8e26b984ef15da906c1303bc8a17bf1e6fef1

shanmuga.m@, could you take a look? I didn't revert the CL.