Remove hardcoded kValueSizeBytes values from variable-length header extensions.

webrtc/modules/rtp_rtcp/include/flexfec_sender.h

 /*
  *  Copyright (c) 2016 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 41 matching lines @@
   // These FEC packets are then obtained by calling GetFecPackets().
   // Returns true if the media packet was successfully added.
   bool AddRtpPacketAndGenerateFec(const RtpPacketToSend& packet);
 
   // Returns true if there are generated FEC packets available.
   bool FecAvailable() const;
 
   // Returns generated FlexFEC packets.
   std::vector<std::unique_ptr<RtpPacketToSend>> GetFecPackets();
 
-  // Returns the overhead, per packet, for FlexFEC.
-  size_t MaxPacketOverhead() const;
+  // Returns the overhead, per packet, for FlexFEC. |extension_sizes| is used
+  // to calculate the RTP header extension overhead and it should have an entry
+  // for each extension that a packet might use. If only fixed-length extensions
+  // are used, |extension_sizes| should be the same at each call.
+  size_t MaxPacketOverhead(
+      rtc::ArrayView<const RtpExtensionSize> extension_sizes) const;
 
  private:
   // Utility.
   Clock* const clock_;
   Random random_;
   int64_t last_generated_packet_ms_;
 
   // Config.
   const int payload_type_;
   const uint32_t timestamp_offset_;
   const uint32_t ssrc_;
   const uint32_t protected_media_ssrc_;
   // Sequence number of next packet to generate.
   uint16_t seq_num_;
 
   // Implementation.
   UlpfecGenerator ulpfec_generator_;
   const RtpHeaderExtensionMap rtp_header_extension_map_;
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_RTP_RTCP_INCLUDE_FLEXFEC_SENDER_H_