Use VoiceChannel/VideoChannel directly from RtpSender/RtpReceiver.

webrtc/api/BUILD.gn

 # Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
 #
 # Use of this source code is governed by a BSD-style license
 # that can be found in the LICENSE file in the root of the source
 # tree. An additional intellectual property rights grant can be found
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
 import("../build/webrtc.gni")
 
@@ skipping 37 matching lines @@
     "localaudiosource.h",
     "mediaconstraintsinterface.cc",
     "mediaconstraintsinterface.h",
     "mediacontroller.cc",
     "mediacontroller.h",
     "mediastream.cc",
     "mediastream.h",
     "mediastreaminterface.h",
     "mediastreamobserver.cc",
     "mediastreamobserver.h",
-    "mediastreamprovider.h",
     "mediastreamproxy.h",
     "mediastreamtrack.h",
     "mediastreamtrackproxy.h",
     "notifier.h",
     "peerconnection.cc",
     "peerconnection.h",
     "peerconnectionfactory.cc",
     "peerconnectionfactory.h",
     "peerconnectionfactoryproxy.h",
     "peerconnectioninterface.h",
@@ skipping 59 matching lines @@
       "quicdatachannel.h",
       "quicdatatransport.cc",
       "quicdatatransport.h",
     ]
     deps += [ "//third_party/libquic" ]
     public_deps = [
       "//third_party/libquic",
     ]
   }
 }