Update comments and doc mentioning AudioProcessingBuilder accordingly Bug: webrtc:369904700 Change-Id: If837ddace5fedce94853c80500c6a832de8db9c7 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/367520 Reviewed-by: Harald Alvestrand <hta@webrtc.org> Commit-Queue: Danil Chapovalov <danilchap@webrtc.org> Cr-Commit-Position: refs/heads/main@{#43376}