Refactor: simplify interface of SenderRtcpSession and CastTransport.

media/cast/sender/audio_sender.cc

Index: media/cast/sender/audio_sender.cc
diff --git a/media/cast/sender/audio_sender.cc b/media/cast/sender/audio_sender.cc
index 808b5ea2e7e662abf8572d4522eabf83b301842a..f253057ec74807725355109f5451ed5608fd878b 100644
--- a/media/cast/sender/audio_sender.cc
+++ b/media/cast/sender/audio_sender.cc
@@ -8,6 +8,7 @@
 
 #include "base/bind.h"
 #include "base/logging.h"
+#include "base/memory/ptr_util.h"
 #include "base/message_loop/message_loop.h"
 #include "media/cast/common/rtp_time.h"
 #include "media/cast/net/cast_transport_config.h"
@@ -16,6 +17,36 @@
 namespace media {
 namespace cast {
 
+namespace {
+
+class AudioSenderRtcpClient : public RtpSenderRtcpClient {

[miu, 2016/04/15 23:14:39]

This is duplicate code (same as in VideoSender).  So, can you just write it once
for FrameSender?  See comment below...

[xjz, 2016/04/20 01:09:03]

Done.

+ public:
+  explicit AudioSenderRtcpClient(base::WeakPtr<AudioSender> audio_sender)
+      : audio_sender_(audio_sender) {}
+
+  void OnCastMessageReceived(const RtcpCastMessage& cast_message) override {
+    if (audio_sender_)
+      audio_sender_->OnReceivedCastFeedback(cast_message);
+  }
+
+  void OnRttReceived(base::TimeDelta round_trip_time) override {
+    if (audio_sender_)
+      audio_sender_->OnMeasuredRoundTripTime(round_trip_time);
+  }
+
+  void OnPliReceived() override {
+    if (audio_sender_)
+      audio_sender_->OnReceivedPli();
+  }
+
+ private:
+  base::WeakPtr<AudioSender> audio_sender_;
+
+  DISALLOW_COPY_AND_ASSIGN(AudioSenderRtcpClient);
+};
+
+}  // namespace
+
 AudioSender::AudioSender(scoped_refptr<CastEnvironment> cast_environment,
                          const AudioSenderConfig& audio_config,
                          const StatusChangeCallback& status_change_cb,
@@ -68,16 +99,13 @@ AudioSender::AudioSender(scoped_refptr<CastEnvironment> cast_environment,
   transport_config.aes_iv_mask = audio_config.aes_iv_mask;
 
   transport_sender->InitializeAudio(
-      transport_config, base::Bind(&AudioSender::OnReceivedCastFeedback,
-                                   weak_factory_.GetWeakPtr()),
-      base::Bind(&AudioSender::OnMeasuredRoundTripTime,
-                 weak_factory_.GetWeakPtr()),
-      base::Bind(&AudioSender::OnReceivedPli, weak_factory_.GetWeakPtr()));
+      transport_config,
+      base::WrapUnique(new AudioSenderRtcpClient(weak_factory_.GetWeakPtr())));
 }
 
 AudioSender::~AudioSender() {}
 
-void AudioSender::InsertAudio(scoped_ptr<AudioBus> audio_bus,
+void AudioSender::InsertAudio(std::unique_ptr<AudioBus> audio_bus,
                               const base::TimeTicks& recorded_time) {
   DCHECK(cast_environment_->CurrentlyOn(CastEnvironment::MAIN));