Layout test svg/dom/SVGScriptElement/script-change-externalResourcesRequired-while-loading.svg is timing out very frequently on GTK port. It's been happening for a long time, but has become more frequent since r215088 "[GTK] Update the priorities used in glib main loop sources". That could be a coincidence -- it could be some other nearby commit -- but it seems like a pretty likely suspect anyway. Updating expectations accordingly.
*** This bug has been marked as a duplicate of bug 191293 ***