Pass the media transport from JsepTransportController to Call.

Add TargetRateObservers for media transport in the call object.



Bug: webrtc:9719
Change-Id: I5448d05359cf09b8cd2a678b2ac876aa8f8970e7
Reviewed-on: https://webrtc-review.googlesource.com/c/110622
Reviewed-by: Steve Anton <steveanton@webrtc.org>
Reviewed-by: Niels Moller <nisse@webrtc.org>
Reviewed-by: Anton Sukhanov <sukhanov@webrtc.org>
Commit-Queue: Peter Slatala <psla@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#25662}
diff --git a/call/call.h b/call/call.h
index 40941e0..5cbbe90 100644
--- a/call/call.h
+++ b/call/call.h
@@ -58,6 +58,11 @@
 
   virtual AudioSendStream* CreateAudioSendStream(
       const AudioSendStream::Config& config) = 0;
+
+  // Gets called when media transport is created or removed.
+  virtual void MediaTransportChange(
+      MediaTransportInterface* media_transport_interface) = 0;
+
   virtual void DestroyAudioSendStream(AudioSendStream* send_stream) = 0;
 
   virtual AudioReceiveStream* CreateAudioReceiveStream(