20cb0c1c85
Previously in the spec, there was a createDtmfSender method on PeerConnection, but that's been replaced by a "dtmf" attribute on RtpSender, which allows getting a DTMF sender without having an audio track. This also simplifies the code slightly, since tracks are now not necessary for identification. BUG=webrtc:4180 Review-Url: https://codereview.webrtc.org/2666853002 Cr-Commit-Position: refs/heads/master@{#16409}