[Cast] Clean-up: Move max_unacked_frames into CongestionControl.

media/cast/sender/congestion_control.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MEDIA_CAST_CONGESTION_CONTROL_CONGESTION_CONTROL_H_
 #define MEDIA_CAST_CONGESTION_CONTROL_CONGESTION_CONTROL_H_
 
 #include <deque>
 
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/time/tick_clock.h"
 #include "base/time/time.h"
 
 namespace media {
 namespace cast {
 
 class CongestionControl {
  public:
   virtual ~CongestionControl();
 
   // Called with latest measured rtt value.
   virtual void UpdateRtt(base::TimeDelta rtt) = 0;
 
+  // Called with an updated target playout delay value.
+  virtual void UpdateTargetPlayoutDelay(base::TimeDelta delay) = 0;
+
   // Called when an encoded frame is sent to the transport.
   virtual void SendFrameToTransport(uint32 frame_id,
                                     size_t frame_size,
                                     base::TimeTicks when) = 0;
   // Called when we receive an ACK for a frame.
   virtual void AckFrame(uint32 frame_id, base::TimeTicks when) = 0;
 
   // Returns the bitrate we should use for the next frame.
   virtual uint32 GetBitrate(base::TimeTicks playout_time,
                             base::TimeDelta playout_delay) = 0;
 };
 
 CongestionControl* NewAdaptiveCongestionControl(
     base::TickClock* clock,
     uint32 max_bitrate_configured,
     uint32 min_bitrate_configured,
-    size_t max_unacked_frames);
+    double max_frame_rate);
 
 CongestionControl* NewFixedCongestionControl(uint32 bitrate);
 
 }  // namespace cast
 }  // namespace media
 
 #endif  // MEDIA_CAST_CONGESTION_CONTROL_CONGESTION_CONTROL_H_