- Clean up unused voice engine DTMF code following removal of VoEDtmf APIs.
- Use better types in AudioSendStream::SendTelephoneEvent() and related methods.

BUG=webrtc:4690

Review URL: https://codereview.webrtc.org/1722253002

Cr-Original-Commit-Position: refs/heads/master@{#11927}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: 8886c816582a7c6190c5429222cb8096fca302a6
21 files changed