The tests didn't pass with requests<2.3 because of the cookies
monkey-patching.
To test this, make sure the requests library in your tox venv is
the right level:
$ .tox/py27/bin/pip install -U "requests<2.3"
Then run the tests.
Closes-Bug: 1442919
Change-Id: Ie93906ba2370dada2386a50ae2137337ccf98f10