Revert of WebRTC: Use the MediaStream Recording API for the audio_quality_browsertest. (patchset #8 id:140001 of https://codereview.chromium.org/2753543010/ )

Reason for revert:
This might be causing failures in Win7 bots:

https://build.chromium.org/p/chromium.webrtc/builders/Win7%20Tester/builds/34106

Original issue's description:
> WebRTC: Use the MediaStream Recording API for the audio_quality_browsertest.
>
> This CL uses the MediaStream Recording API to record the audio received
> by the right tag. It saves it as a webm file that is later converted to a
> wav file using ffmpeg.
>
> This might cause a performance regression because we're using webm+ffmpeg
> to generate the wav file. I set a, hopefully high enough, bitrate to
> mitigate this
>
> BUG=chromium:681577
> NOTRY=True
>
> Review-Url: https://codereview.chromium.org/2753543010
> Cr-Commit-Position: refs/heads/master@{#459050}
> Committed: https://chromium.googlesource.com/chromium/src/+/a0a47bfebb016ec468bc6d1b4be9b1acb22a4075

TBR=kjellander@chromium.org,hbos@chromium.org,mcasas@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=chromium:681577

Review-Url: https://codereview.chromium.org/2773803002
Cr-Commit-Position: refs/heads/master@{#459234}
4 files changed