WebDriver process killed before the Command.QUIT sent to it

Originally posted as https://github.com/w3c/wptrunner/issues/175 by @lizzygao on 24 Mar 2016, 03:02 UTC:

Run the wptrunner and take the Chrome as the product, like this:

wptrunner --metadata=tests\ --tests=tests\ --binary="C:\Program Files (x86)\Google\Chrome\Application\chrome.exe" --product=chrome --webdriver-binary="C:\Users\ygao\bin\chromedriver.exe" --include=2dcontext --processes=1 --log-raw=log-raw.txt > test.txt

Some errors come up about:
URLError:
urlopen error [Errno 10061] No connection could be made because the target machine actively refused it

It caused by the WebDriver process (LocalServer.stop) is killed, and then the QUIT command sent to it (SeleniumProtocol.teardown)

This behavior is not suitable for the QUIT is never working on the WebDriver server side.

Is this an considering issue and being fixed?

Start by reproducing the Windows wptrunner command from the issue with Chrome and one process. Trace LocalServer.stop and SeleniumProtocol.teardown to confirm the WebDriver process lifecycle; done means teardown sends Command.QUIT while the server is still available and avoids the connection-refused error.