This CL reverts the changes introduced that handles echoes in AEC3.
The revert is done to match the behavior which is in M63.
Bug: webrtc:8615,chromium:792346
Change-Id: I128ccb17dc359c7889a701a2faaaf06be40f86dd
Reviewed-on: https://webrtc-review.googlesource.com/30140
Commit-Queue: Per Åhgren <peah@webrtc.org>
Reviewed-by: Gustaf Ullberg <gustaf@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#21117}