Revert "audio_processing/aec: make delay estimator aware of starving farend buffer"

The code only affects DA-AEC, but since DA-AEC is the default AEC if run on Android tests failed. Reverting to fix that test.

This reverts commit 9002cc426dab7a576f5247f45ba888cd081a39f0.

BUG=
TBR=henrik.lundin@webrtc.org

Review URL: https://codereview.webrtc.org/1183243003.

Cr-Commit-Position: refs/heads/master@{#9453}
2 files changed