Update the BWE when the network route changes.

BUG=

Review-Url: https://codereview.webrtc.org/2000063003
Cr-Original-Commit-Position: refs/heads/master@{#13021}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: 2221e1cd1dd19ae16c87c14bbea92fa62d15154d
8 files changed