Revert of Reimplement the builtin audio codec factories using the new stuff in api/ (patchset #1 id:60001 of https://codereview.webrtc.org/2997713002/ )

Reason for revert:
Speculatively reverting, likely breaks chromium.webrtc.fyi.

Failed to create local offer: Test failed: Error: setSdpDefaultCodec() failed: "Unknown ID for |codec| = 'G722'."

Failing bots:
https://build.chromium.org/p/chromium.webrtc.fyi/builders/Mac%20Tester/builds/42349
https://build.chromium.org/p/chromium.webrtc.fyi/builders/Win8%20Tester/builds/1561
https://build.chromium.org/p/chromium.webrtc.fyi/builders/Win10%20Tester/builds/8517

Original issue's description:
> Reimplement the builtin audio codec factories using the new stuff in api/
>
> The whole point of all the audio codec stuff we've recently published
> in api/ is to function as lego bricks so that building stuff like our
> builtin audio codec factories will be easy.
>
> BUG=webrtc:7821, webrtc:7822
>
> Review-Url: https://codereview.webrtc.org/2997713002
> Cr-Commit-Position: refs/heads/master@{#19446}
> Committed: https://chromium.googlesource.com/external/webrtc/+/417989a8643d0d19052a87e95905b469d5ede173

TBR=ossu@webrtc.org,kwiberg@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=webrtc:7821, webrtc:7822

Review-Url: https://codereview.webrtc.org/2996373002
Cr-Original-Commit-Position: refs/heads/master@{#19452}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: bcc655c2c71bb1df2ef94cdbf126b318135f1920
10 files changed