Re: [infra-tests] Add codecov configuration. (#5623)

# [Codecov](https://codecov.io/gh/w3c/web-platform-tests/pull/5623?src=pr&el=h1) Report
> Merging [#5623](https://codecov.io/gh/w3c/web-platform-tests/pull/5623?src=pr&el=desc) into [master](https://codecov.io/gh/w3c/web-platform-tests/commit/1d677e397df5e57bfc127a17b8828e3ba5062cc7?src=pr&el=desc) will **not change** coverage.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/w3c/web-platform-tests/pull/5623/graphs/tree.svg?width=650&height=150&src=pr&token=DI3aecdnSC)](https://codecov.io/gh/w3c/web-platform-tests/pull/5623?src=pr&el=tree)

```diff
@@           Coverage Diff           @@
##           master    #5623   +/-   ##
=======================================
  Coverage   87.22%   87.22%           
=======================================
  Files          24       24           
  Lines        2418     2418           
  Branches      406      406           
=======================================
  Hits         2109     2109           
  Misses        239      239           
  Partials       70       70
```



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[Continue to review full report at Codecov](https://codecov.io/gh/w3c/web-platform-tests/pull/5623?src=pr&el=continue).
> **Legend** - [Click here to learn more](https://docs.codecov.io/docs/codecov-delta)
> `Δ = absolute <relative> (impact)`, `ø = not affected`, `? = missing data`
> Powered by [Codecov](https://codecov.io/gh/w3c/web-platform-tests/pull/5623?src=pr&el=footer). Last update [1d677e3...246c4f9](https://codecov.io/gh/w3c/web-platform-tests/pull/5623?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).


View on GitHub: https://github.com/w3c/web-platform-tests/pull/5623#issuecomment-295781893

Received on Thursday, 20 April 2017 15:33:32 UTC