Cleanup RtpHeaderExtensionMap removing use of two legacy functions

webrtc/modules/rtp_rtcp/source/rtp_header_extension.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.
  */
 
@@ skipping 59 matching lines @@
     return ids_[type];
   }
 
   size_t GetTotalLengthInBytes() const;
 
   // TODO(danilchap): Remove use of the functions below.
   int32_t Register(RTPExtensionType type, uint8_t id) {
     return RegisterByType(id, type) ? 0 : -1;
   }
   int32_t Deregister(RTPExtensionType type);
-  int32_t GetType(uint8_t id, RTPExtensionType* type) const {
-    *type = GetType(id);
-    return *type == kInvalidType ? -1 : 0;
-  }
-  void GetCopy(RtpHeaderExtensionMap* copy) const { *copy = *this; }
 
  private:
   static constexpr uint8_t kMinId = 1;
   static constexpr uint8_t kMaxId = 14;
   bool Register(uint8_t id,
                 RTPExtensionType type,
                 size_t value_size,
                 const char* uri);
 
   size_t total_values_size_bytes_ = 0;
   RTPExtensionType types_[kMaxId + 1];
   uint8_t ids_[kRtpExtensionNumberOfExtensions];
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_RTP_RTCP_SOURCE_RTP_HEADER_EXTENSION_H_