Adding "adapter" ORTC objects on top of ChannelManager/BaseChannel/etc.

webrtc/media/sctp/sctptransport.cc

Index: webrtc/media/sctp/sctptransport.cc
diff --git a/webrtc/media/sctp/sctptransport.cc b/webrtc/media/sctp/sctptransport.cc
index f967c2aba7974a7bfcfd72cf34a8c09528d455cc..ae69628a98b8a0031f1fe0d57ac5b5b92bf42bdf 100644
--- a/webrtc/media/sctp/sctptransport.cc
+++ b/webrtc/media/sctp/sctptransport.cc
@@ -385,7 +385,7 @@ class SctpTransport::UsrSctpWrapper {
 };
 
 SctpTransport::SctpTransport(rtc::Thread* network_thread,
-                             rtc::PacketTransportInterface* channel)
+                             rtc::PacketTransportInternal* channel)
     : network_thread_(network_thread),
       transport_channel_(channel),
       was_ever_writable_(channel->writable()) {
@@ -400,8 +400,7 @@ SctpTransport::~SctpTransport() {
   CloseSctpSocket();
 }
 
-void SctpTransport::SetTransportChannel(
-    rtc::PacketTransportInterface* channel) {
+void SctpTransport::SetTransportChannel(rtc::PacketTransportInternal* channel) {
   RTC_DCHECK_RUN_ON(network_thread_);
   RTC_DCHECK(channel);
   DisconnectTransportChannelSignals();
@@ -808,7 +807,7 @@ void SctpTransport::SetReadyToSendData() {
   }
 }
 
-void SctpTransport::OnWritableState(rtc::PacketTransportInterface* transport) {
+void SctpTransport::OnWritableState(rtc::PacketTransportInternal* transport) {
   RTC_DCHECK_RUN_ON(network_thread_);
   RTC_DCHECK_EQ(transport_channel_, transport);
   if (!was_ever_writable_ && transport->writable()) {
@@ -820,7 +819,7 @@ void SctpTransport::OnWritableState(rtc::PacketTransportInterface* transport) {
 }
 
 // Called by network interface when a packet has been received.
-void SctpTransport::OnPacketRead(rtc::PacketTransportInterface* transport,
+void SctpTransport::OnPacketRead(rtc::PacketTransportInternal* transport,
                                  const char* data,
                                  size_t len,
                                  const rtc::PacketTime& packet_time,