Revert "bpo-36801: Fix waiting in StreamWriter.drain for closing SSL transport (GH-13098)"

[vstinner]

This reverts commit 1cc0ee7.

https://bugs.python.org/issue36801

[vstinner]

I already reverted the change in 3.7: PR #13328.

The revert in master is motivated by https://bugs.python.org/issue36870 : test_asyncio fails randomly which causes a lot of pain in the Python CI and the Python workflow.

I don't know yet if PR #13313 fixed https://bugs.python.org/issue36870

[asvetlov]

I don't know yet if PR #13313 fixed https://bugs.python.org/issue36870

I guess no, the PR #13313 doesn't fix your issue.
This pull request is necessary (but please don't revert #13313 and #13099)

[asvetlov]

#13330 is a minimal change that reverts StreamWriter.drain() on the master to code that was working properly.
I suggest to use it instead, tests should pass

[vstinner]

I suggest to use it instead, tests should pass

Honestly, I don't care: it's up to you, as soon as test_asyncio pass: as soon as https://bugs.python.org/issue36870 is fixed.

[vstinner]

@asvetlov merged PR #13330 instead. I close this PR.