Drop streamreader payload

[asvetlov]

Fix for #2557

[codecov-io]

Codecov Report

Merging #2558 into master will increase coverage by 0.09%.
The diff coverage is 100%.

@@            Coverage Diff            @@
##           master   #2558      +/-   ##
=========================================
+ Coverage   97.31%   97.4%   +0.09%     
=========================================
  Files          40      40              
  Lines        8087    8068      -19     
  Branches     1421    1419       -2     
=========================================
- Hits         7870    7859      -11     
+ Misses         89      81       -8     
  Partials      128     128

Impacted Files	Coverage Δ
aiohttp/payload.py	98.71% <100%> (+4.43%)	⬆️

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This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a [new issue] for related bugs.
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[new issue]: https://github.com/aio-libs/aiohttp/issues/new