This CL removes the field trial left in place as a kill-switch in case there were any regressions related to selecting payload padding based on the likelihood of being useful instead of matching size. It also removes the functionality that was only enabled with the kill-switch active. The feature has been default-on since June 23rd 2019: https://webrtc.googlesource.com/src.git/+/214f54365ec210db76218a35ead66c9ce23e068e Since we have not observed any issues, let's clean this code up. Bug: webrtc:8975 Change-Id: I7f49fe354227b3f6566a250332e56b6d70fe2f09 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/145821 Commit-Queue: Erik Språng <sprang@webrtc.org> Reviewed-by: Stefan Holmer <stefan@webrtc.org> Cr-Commit-Position: refs/heads/master@{#28616}