Allowing resetting of AudioNetworkAdaptor in AudioSendStream.

BUG=webrtc:6681

Review-Url: https://codereview.webrtc.org/2495833002
Cr-Original-Commit-Position: refs/heads/master@{#15058}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: 6f0b9fda5343ec31bcc6aba67fb3e8d5f3c4e0e2
2 files changed