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diff --git a/third_party/libwebrtc/modules/video_coding/rtp_frame_reference_finder.h b/third_party/libwebrtc/modules/video_coding/rtp_frame_reference_finder.h
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+++ b/third_party/libwebrtc/modules/video_coding/rtp_frame_reference_finder.h
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+/*
+ *  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.
+ */
+
+#ifndef MODULES_VIDEO_CODING_RTP_FRAME_REFERENCE_FINDER_H_
+#define MODULES_VIDEO_CODING_RTP_FRAME_REFERENCE_FINDER_H_
+
+#include <memory>
+
+#include "modules/rtp_rtcp/source/frame_object.h"
+
+namespace webrtc {
+namespace internal {
+class RtpFrameReferenceFinderImpl;
+}  // namespace internal
+
+class RtpFrameReferenceFinder {
+ public:
+  using ReturnVector = absl::InlinedVector<std::unique_ptr<RtpFrameObject>, 3>;
+
+  RtpFrameReferenceFinder();
+  explicit RtpFrameReferenceFinder(int64_t picture_id_offset);
+  ~RtpFrameReferenceFinder();
+
+  // The RtpFrameReferenceFinder will hold onto the frame until:
+  //  - the required information to determine its references has been received,
+  //    in which case it (and possibly other) frames are returned, or
+  //  - There are too many stashed frames (determined by `kMaxStashedFrames`),
+  //    in which case it gets dropped, or
+  //  - It gets cleared by ClearTo, in which case its dropped.
+  //  - The frame is old, in which case it also gets dropped.
+  ReturnVector ManageFrame(std::unique_ptr<RtpFrameObject> frame);
+
+  // Notifies that padding has been received, which the reference finder
+  // might need to calculate the references of a frame.
+  ReturnVector PaddingReceived(uint16_t seq_num);
+
+  // Clear all stashed frames that include packets older than `seq_num`.
+  void ClearTo(uint16_t seq_num);
+
+ private:
+  void AddPictureIdOffset(ReturnVector& frames);
+
+  // How far frames have been cleared out of the buffer by RTP sequence number.
+  // A frame will be cleared if it contains a packet with a sequence number
+  // older than `cleared_to_seq_num_`.
+  int cleared_to_seq_num_ = -1;
+  const int64_t picture_id_offset_;
+  std::unique_ptr<internal::RtpFrameReferenceFinderImpl> impl_;
+};
+
+}  // namespace webrtc
+
+#endif  // MODULES_VIDEO_CODING_RTP_FRAME_REFERENCE_FINDER_H_