[Cast] Cleanup: Remove TransportXXXXXSender, an unnecessary layer of indirection.

media/cast/audio_sender/audio_sender.h

Index: media/cast/audio_sender/audio_sender.h
diff --git a/media/cast/audio_sender/audio_sender.h b/media/cast/audio_sender/audio_sender.h
index c633b076c8a7edff836f85de206784c45b3e1e98..0ac619df6855c902cfdd7497be7ed6d8efd0c136 100644
--- a/media/cast/audio_sender/audio_sender.h
+++ b/media/cast/audio_sender/audio_sender.h
@@ -16,7 +16,7 @@
 #include "media/cast/cast_config.h"
 #include "media/cast/rtcp/rtcp.h"
 #include "media/cast/rtp_timestamp_helper.h"
-#include "media/cast/transport/rtp_sender/rtp_sender.h"
+#include "media/cast/transport/utility/transport_encryption_handler.h"
 
 namespace media {
 namespace cast {
@@ -36,18 +36,17 @@ class AudioSender : public RtcpSenderFeedback,
   virtual ~AudioSender();
 
   CastInitializationStatus InitializationResult() const {
-    return cast_initialization_cb_;
+    return cast_initialization_status_;
   }
 
+  // Note: It is invalid to call this method if InitializationResult() returns
+  // anything but STATUS_AUDIO_INITIALIZED.
   void InsertAudio(scoped_ptr<AudioBus> audio_bus,
                    const base::TimeTicks& recorded_time);
 
   // Only called from the main cast thread.
   void IncomingRtcpPacket(scoped_ptr<Packet> packet);
 
- protected:
-  void SendEncodedAudioFrame(scoped_ptr<transport::EncodedFrame> audio_frame);
-
  private:
   void ResendPackets(
       const MissingFramesAndPacketsMap& missing_frames_and_packets);
@@ -55,6 +54,11 @@ class AudioSender : public RtcpSenderFeedback,
   void ScheduleNextRtcpReport();
   void SendRtcpReport(bool schedule_future_reports);
 
+  // Called by the |audio_encoder_| with the next EncodedFrame to send.  If
+  // encryption is enabled, |encoded_frame->data| is encrypted before sending
+  // using |transport_sender_|.
+  void SendEncodedAudioFrame(scoped_ptr<transport::EncodedFrame> audio_frame);
+
   virtual void OnReceivedCastFeedback(const RtcpCastMessage& cast_feedback)
       OVERRIDE;
 
@@ -64,7 +68,12 @@ class AudioSender : public RtcpSenderFeedback,
   RtpTimestampHelper rtp_timestamp_helper_;
   Rtcp rtcp_;
   int num_aggressive_rtcp_reports_sent_;
-  CastInitializationStatus cast_initialization_cb_;
+
+  // Encrypts data in EncodedFrames before they are sent.
+  transport::TransportEncryptionHandler encryptor_;
+
+  // If this sender is ready for use, this is STATUS_AUDIO_INITIALIZED.
+  CastInitializationStatus cast_initialization_status_;
 
   // Used to map the lower 8 bits of the frame id to a RTP timestamp. This is
   // good enough as we only use it for logging.