There is no public API to create NetworkBehaviorInterface from BuiltInNetworkBehaviorConfig, so this CL will add direct method, that will allow downstream projects to use BuiltInNetworkBehaviorConfig for network emulation. Bug: webrtc:10138 Change-Id: Iaec3ea17c12bd06b1c0ff3e5bc2b32cc1c4f62f8 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/144628 Reviewed-by: Sebastian Jansson <srte@webrtc.org> Reviewed-by: Karl Wiberg <kwiberg@webrtc.org> Commit-Queue: Artem Titov <titovartem@webrtc.org> Cr-Commit-Position: refs/heads/master@{#28494}