Reason for revert: Reverting because it broke an RTP data channel test on the FYI bots. Original issue's description: > Modified PeerConnection and WebRtcSession for end-to-end QuicDataChannel usage. > > To allow end-to-end QuicDataChannel usage with a > PeerConnection, RTCConfiguration has been modified to > include a boolean for whether to do QUIC, since negotiation of > QUIC is not implemented. If one peer does QUIC, then it will be > assumed that the other peer must do QUIC or the connection > will fail. > > PeerConnection has been modified to create data channels of type > QuicDataChannel when the peer wants to do QUIC. > > WebRtcSession has ben modified to use a QuicDataTransport > instead of a DtlsTransportChannelWrapper/DataChannel > when QUIC should be used > > QuicDataTransport implements the generic functions of > BaseChannel to manage the QuicTransportChannel. > > Committed: https://crrev.com/34b54c36a533dadb6ceb70795119194e6f530ef5 > Cr-Commit-Position: refs/heads/master@{#13645} TBR=pthatcher@webrtc.org,zhihuang@webrtc.org # Skipping CQ checks because original CL landed less than 1 days ago. NOPRESUBMIT=true NOTREECHECKS=true NOTRY=true Review-Url: https://codereview.webrtc.org/2206793007 Cr-Commit-Position: refs/heads/master@{#13647}