Error on scheme access

[AlwxSin]

Hi, thanks for your library.

I encountered a bug when my ws connection closed. If my app tries to write into closed connection concurrent.futures._base.CancelledError raised. And this is ok.
But then aiohttp-sentry doesn't send an error to sentry because of

Traceback (most recent call last):
  ......
  File "/usr/local/lib/python3.6/site-packages/aiohttp_sentry/__init__.py", line 27, in middleware
    extra_data = await self.get_extra_data(request)
  File "/usr/local/lib/python3.6/site-packages/aiohttp_sentry/__init__.py", line 39, in get_extra_data
    'scheme': request.scheme,
  File "/usr/local/lib/python3.6/site-packages/aiohttp/web_request.py", line 290, in scheme
    if self.transport.get_extra_info('sslcontext'):
AttributeError: 'NoneType' object has no attribute 'get_extra_info'

I found the related issue but it seems closed.

Would you mind me create PR where I move request.scheme under if request.transport statement?

[underyx]

Thank you so much for the investigative work, @AlwxSin! Indeed if this is how aiohttp works, we should move the scheme line as you described, like in this similar commit: d7080a8

A pull request would be appreciated. Thank you again!

[AlwxSin]

Done.
Thanks for quick answer.