Move RtpPacketSender and merge it with RtpPacketPacer.

This interface is intended to only handle packet-sending parts of the
paced sender.

See https://webrtc-review.googlesource.com/c/src/+/145212 for context

Bug: webrtc:10809
Change-Id: I93f0b40e1865665c2d436db67021350a0ed0687b
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/145216
Commit-Queue: Erik Språng <sprang@webrtc.org>
Reviewed-by: Stefan Holmer <stefan@webrtc.org>
Reviewed-by: Sebastian Jansson <srte@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#28662}
diff --git a/call/rtp_transport_controller_send.h b/call/rtp_transport_controller_send.h
index e7e1610..3a844ea 100644
--- a/call/rtp_transport_controller_send.h
+++ b/call/rtp_transport_controller_send.h
@@ -76,7 +76,7 @@
 
   NetworkStateEstimateObserver* network_state_estimate_observer() override;
   TransportFeedbackObserver* transport_feedback_observer() override;
-  RtpPacketPacer* packet_sender() override;
+  RtpPacketSender* packet_sender() override;
 
   void SetAllocatedSendBitrateLimits(int min_send_bitrate_bps,
                                      int max_padding_bitrate_bps,
@@ -106,6 +106,8 @@
   void OnTransportOverheadChanged(
       size_t transport_overhead_per_packet) override;
 
+  void AccountForAudioPacketsInPacedSender(bool account_for_audio) override;
+
   // Implements RtcpBandwidthObserver interface
   void OnReceivedEstimatedBitrate(uint32_t bitrate) override;
   void OnReceivedRtcpReceiverReport(const ReportBlockList& report_blocks,