Revert "bpo-36802: Drop awrite()/aclose(), support await write() and await close() instead (#13099)"

[vstinner]

This reverts commit a076e4f.

https://bugs.python.org/issue36802

[vstinner]

This revert is an attempt to fix https://bugs.python.org/issue36870 regression.

[vstinner]

Without this change, python -m test test_asyncio -m test_drain_raises -v pass but logs a warning on my Windows VM:

test_drain_raises (test.test_asyncio.test_streams.StreamTests) ... Task exception was never retrieved
future: <Task finished name='Task-2' coro=<StreamWriter.drain() done, defined at C:\vstinner\python\master\lib\asyncio\streams.py:417> exception=ConnectionAbor
tedError(10053, 'An established connection was aborted by the software in your host machine', None, 10053, None)>
Traceback (most recent call last):
File "C:\vstinner\python\master\lib\asyncio\streams.py", line 434, in drain
await fut
File "C:\vstinner\python\master\lib\asyncio\proactor_events.py", line 370, in _loop_writing
self._write_fut = self._loop._proactor.send(self._sock, data)
File "C:\vstinner\python\master\lib\asyncio\windows_events.py", line 488, in send
ov.WSASend(conn.fileno(), buf, flags)
ConnectionAbortedError: [WinError 10053] An established connection was aborted by the software in your host machine

With this PR, it pass but doesn't log any warning.

[asvetlov]

Please take a look on #13313
I believe it has a proper fix for messages generated by test_drain_raises()

[vstinner]

I merged PR #13313 instead.