Reland of Rename RTPVideoHeader.isFirstPacket to .is_first_packet_in_frame.

webrtc/modules/video_coding/frame_buffer.cc

 /*
  *  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 143 matching lines @@
   // The MTSI client shall add the payload bytes as defined in this clause
   // onto the last RTP packet in each group of packets which make up a key
   // frame (I-frame or IDR frame in H.264 (AVC), or an IRAP picture in H.265
   // (HEVC)).
   if (packet.markerBit) {
     RTC_DCHECK(!_rotation_set);
     rotation_ = packet.video_header.rotation;
     _rotation_set = true;
   }
 
-  if (packet.isFirstPacket) {
+  if (packet.is_first_packet_in_frame) {
     playout_delay_ = packet.video_header.playout_delay;
   }
 
   if (_sessionInfo.complete()) {
     SetState(kStateComplete);
     return kCompleteSession;
   } else if (_sessionInfo.decodable()) {
     SetState(kStateDecodable);
     return kDecodableSession;
   }
@@ skipping 85 matching lines @@
   size_t bytes_removed = _sessionInfo.MakeDecodable();
   _length -= bytes_removed;
   // Transfer frame information to EncodedFrame and create any codec
   // specific information.
   _frameType = _sessionInfo.FrameType();
   _completeFrame = _sessionInfo.complete();
   _missingFrame = !continuous;
 }
 
 }  // namespace webrtc