Revert of Re-enable UBsan on AGC. (patchset #8 id:300001 of https://codereview.webrtc.org/2003623003/ )

Reason for revert:
Breaks bot.

Original issue's description:
> Re-enable UBsan on AGC.
>
> BUG=webrtc:5530
>
> Committed: https://crrev.com/293c86d67384c15f46b8296096a62a14b4a58d33
> Cr-Commit-Position: refs/heads/master@{#13034}

R=kjellander@webrtc.org, peah@webrtc.org
TBR=kjellander@webrtc.org, minyue@webrtc.org, peah@webrtc.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=webrtc:5530

Review URL: https://codereview.webrtc.org/2056683002 .

Cr-Original-Commit-Position: refs/heads/master@{#13096}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: 2b9423f7a18145255deb93f2505a4fd1c3fa9ad7
3 files changed