Revert "AEC3: Reduce filter divergence during low-echo double-talk"
Revert "AEC3: Reduce filter divergence during low-echo double-talk"

This reverts commit 958ed238603ba5a2937d28ce1c9281920d923019.

Reason for revert: Will need additional work to handle clock-drift.

Original change's description:
> AEC3: Reduce filter divergence during low-echo double-talk
> 
> Bug: webrtc:9746,chromium:883264
> Change-Id: Ie3faf106fd1fd835e67d9e6794c679703af54fea
> Reviewed-on: https://webrtc-review.googlesource.com/99920
> Reviewed-by: Per Åhgren <peah@webrtc.org>
> Commit-Queue: Gustaf Ullberg <3619ad972adf2eeb42172b0d9b4d612d59d226c7@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#24706}

TBR=3619ad972adf2eeb42172b0d9b4d612d59d226c7@webrtc.org,peah@webrtc.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: webrtc:9746, chromium:883264
Change-Id: Ib039eb80e2ddfc43ec52183086da2474baef65e0
Reviewed-on: https://webrtc-review.googlesource.com/100480
Reviewed-by: Gustaf Ullberg <3619ad972adf2eeb42172b0d9b4d612d59d226c7@webrtc.org>
Commit-Queue: Gustaf Ullberg <3619ad972adf2eeb42172b0d9b4d612d59d226c7@webrtc.org>
Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#24741}
ShiftMediaProject/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,TimothyGu/libilbc