This change adds a percentile filter that can replace the "non-linear IIR" filter that is currently used to estimate the max frame size (in bytes). The percentile filter is enabled through the field trial, and it has two tuning parameters: the percentile that is deemed the "max" frame, and the window length over which the filter is applied. Bug: webrtc:14151 Change-Id: I002609edb0a74161aaa6f0934892a1bec2ad8230 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/274167 Reviewed-by: Philip Eliasson <philipel@webrtc.org> Commit-Queue: Rasmus Brandt <brandtr@webrtc.org> Cr-Commit-Position: refs/heads/main@{#38047}