This change adds a median filter that can replace the IIR filter that is currently used to estimate the avg frame size (in bytes). It is enabled through a boolean, and reuses the window length from the max percentile filter. The median filter is only used by the delay calculation in `CalculateEstimate()`. It does not replaced the use of the IIR estimate in the size outlier rejection heuristic. Bug: webrtc:14151 Change-Id: I519b6b57a8bee3c41a300ed2e92a1981c61cca15 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/275121 Reviewed-by: Philip Eliasson <philipel@webrtc.org> Commit-Queue: Rasmus Brandt <brandtr@webrtc.org> Cr-Commit-Position: refs/heads/main@{#38077}