Flaky tests in Python 3.5.0 with xdist 😬

[nicoddemus]

__________________________ testing/test_collection.py __________________________
[gw1] linux -- Python 3.5.0 /home/travis/build/pytest-dev/pytest/.tox/py35-xdist/bin/python
worker 'gw1' crashed while running 'testing/test_collection.py::test_exit_on_collection_with_maxfail_bigger_than_n_errors'

https://travis-ci.org/pytest-dev/pytest/jobs/577770604

😬

---

In #5803 (comment), we suspect this is related to 3.5.0, as we have never seen this failure before started testing on that Python version on Travis.

[nicoddemus]

Unfortunately py35, without xdist and coverage, still is crashing randomly.

Unless someone has other ideas, I think we should consider not testing Python 3.5.0 anymore. Having it failing randomly is too disruptive.

Does flake8 now cover most gotchas related to poor typing in 3.5.0?