Revert of Remove unnecessary interface TelephoneEventHandler

webrtc/modules/rtp_rtcp/include/rtp_receiver.h

 /*
  *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
 #ifndef WEBRTC_MODULES_RTP_RTCP_INCLUDE_RTP_RECEIVER_H_
 #define WEBRTC_MODULES_RTP_RTCP_INCLUDE_RTP_RECEIVER_H_
 
 #include "webrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.h"
 #include "webrtc/typedefs.h"
 
 namespace webrtc {
 
 class RTPPayloadRegistry;
 
+class TelephoneEventHandler {
+ public:
+  virtual ~TelephoneEventHandler() {}
+
+  // The following three methods implement the TelephoneEventHandler interface.
+  // Forward DTMFs to decoder for playout.
+  virtual void SetTelephoneEventForwardToDecoder(bool forward_to_decoder) = 0;
+
+  // Is forwarding of outband telephone events turned on/off?
+  virtual bool TelephoneEventForwardToDecoder() const = 0;
+
+  // Is TelephoneEvent configured with payload type payload_type
+  virtual bool TelephoneEventPayloadType(const int8_t payload_type) const = 0;
+};
+
 class RtpReceiver {
  public:
   // Creates a video-enabled RTP receiver.
   static RtpReceiver* CreateVideoReceiver(
       Clock* clock,
       RtpData* incoming_payload_callback,
       RtpFeedback* incoming_messages_callback,
       RTPPayloadRegistry* rtp_payload_registry);
 
   // Creates an audio-enabled RTP receiver.
   static RtpReceiver* CreateAudioReceiver(
       Clock* clock,
       RtpData* incoming_payload_callback,
       RtpFeedback* incoming_messages_callback,
       RTPPayloadRegistry* rtp_payload_registry);
 
   virtual ~RtpReceiver() {}
 
+  // Returns a TelephoneEventHandler if available.
+  virtual TelephoneEventHandler* GetTelephoneEventHandler() = 0;
+
   // Registers a receive payload in the payload registry and notifies the media
   // receiver strategy.
   virtual int32_t RegisterReceivePayload(
       const char payload_name[RTP_PAYLOAD_NAME_SIZE],
       const int8_t payload_type,
       const uint32_t frequency,
       const size_t channels,
       const uint32_t rate) = 0;
 
   // De-registers |payload_type| from the payload registry.
@@ skipping 20 matching lines @@
 
   // Returns the current remote CSRCs.
   virtual int32_t CSRCs(uint32_t array_of_csrc[kRtpCsrcSize]) const = 0;
 
   // Returns the current energy of the RTP stream received.
   virtual int32_t Energy(uint8_t array_of_energy[kRtpCsrcSize]) const = 0;
 };
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_RTP_RTCP_INCLUDE_RTP_RECEIVER_H_