http/tests/xmlhttprequest/timeout/xmlhttprequest-timeout-overridesexpires.html flakily fails on slower bots:
-PASS XHR2 Timeout Property Tests
-PASS XHR2 Timeout Property Tests 1
+FAIL XHR2 Timeout Property Tests assert_equals: timeout set to expiring value after load fires, original timeout at 1000, reset at 800 to 200 expected "load" but got "timeout"(stack: assert@http://127.0.0.1:8000/w3c/resources/testharness.js:2060:37
This is not very recent, it happened on August 22nd (and possibly before that).
Marked as flaky in r189638.
Will have a look at it, probably next week.
FWIW, the timeouts of the corresponding W3C tests got increased 5x, probably for similar reasons (https://github.com/w3c/web-platform-tests/commit/b74228224b0411069050cb81b3d74fc205c59339).
I guess doing so might increase the risk of getting timeouting tests for all xmlhttprequest/timeout tests if not updating TestExpectations.
We might want to try increasing timeouts, by 2x or 3x.
WebKit xmlhttprequest-timeout-overridesexpires.html was removed in favor of WPT version which is not flaky (increased timeouts).