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diff --git a/third_party/libwebrtc/api/video_codecs/vp8_frame_config.h b/third_party/libwebrtc/api/video_codecs/vp8_frame_config.h
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+++ b/third_party/libwebrtc/api/video_codecs/vp8_frame_config.h
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+/*
+ *  Copyright (c) 2019 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 API_VIDEO_CODECS_VP8_FRAME_CONFIG_H_
+#define API_VIDEO_CODECS_VP8_FRAME_CONFIG_H_
+
+#include <stdint.h>
+
+namespace webrtc {
+
+// Configuration of a VP8 frame - which buffers are to be referenced
+// by it, which buffers should be updated, etc.
+struct Vp8FrameConfig {
+  static Vp8FrameConfig GetIntraFrameConfig() {
+    Vp8FrameConfig frame_config = Vp8FrameConfig(
+        BufferFlags::kUpdate, BufferFlags::kUpdate, BufferFlags::kUpdate);
+    frame_config.packetizer_temporal_idx = 0;
+    return frame_config;
+  }
+
+  enum BufferFlags : int {
+    kNone = 0,
+    kReference = 1,
+    kUpdate = 2,
+    kReferenceAndUpdate = kReference | kUpdate,
+  };
+
+  enum FreezeEntropy { kFreezeEntropy };
+
+  // Defined bit-maskable reference to the three buffers available in VP8.
+  enum class Vp8BufferReference : uint8_t {
+    kNone = 0,
+    kLast = 1,
+    kGolden = 2,
+    kAltref = 4
+  };
+
+  Vp8FrameConfig();
+
+  Vp8FrameConfig(BufferFlags last, BufferFlags golden, BufferFlags arf);
+  Vp8FrameConfig(BufferFlags last,
+                 BufferFlags golden,
+                 BufferFlags arf,
+                 FreezeEntropy);
+
+  enum class Buffer : int { kLast = 0, kGolden = 1, kArf = 2, kCount };
+
+  bool References(Buffer buffer) const;
+
+  bool Updates(Buffer buffer) const;
+
+  bool IntraFrame() const {
+    // Intra frames do not reference any buffers, and update all buffers.
+    return last_buffer_flags == kUpdate && golden_buffer_flags == kUpdate &&
+           arf_buffer_flags == kUpdate;
+  }
+
+  bool drop_frame;
+  BufferFlags last_buffer_flags;
+  BufferFlags golden_buffer_flags;
+  BufferFlags arf_buffer_flags;
+
+  // The encoder layer ID is used to utilize the correct bitrate allocator
+  // inside the encoder. It does not control references nor determine which
+  // "actual" temporal layer this is. The packetizer temporal index determines
+  // which layer the encoded frame should be packetized into.
+  // Normally these are the same, but current temporal-layer strategies for
+  // screenshare use one bitrate allocator for all layers, but attempt to
+  // packetize / utilize references to split a stream into multiple layers,
+  // with different quantizer settings, to hit target bitrate.
+  // TODO(sprang): Screenshare layers are being reconsidered at the time of
+  // writing, we might be able to remove this distinction, and have a temporal
+  // layer imply both (the normal case).
+  int encoder_layer_id;
+  // TODO(eladalon/sprang): Move out of this class.
+  int packetizer_temporal_idx;
+
+  // TODO(eladalon/sprang): Move out of this class.
+  bool layer_sync;
+
+  bool freeze_entropy;
+
+  // Indicates in which order the encoder should search the reference buffers
+  // when doing motion prediction. Set to kNone to use unspecified order. Any
+  // buffer indicated here must not have the corresponding no_ref bit set.
+  // If all three buffers can be reference, the one not listed here should be
+  // searched last.
+  Vp8BufferReference first_reference;
+  Vp8BufferReference second_reference;
+
+  // Whether this frame is eligible for retransmission.
+  bool retransmission_allowed;
+
+ private:
+  Vp8FrameConfig(BufferFlags last,
+                 BufferFlags golden,
+                 BufferFlags arf,
+                 bool freeze_entropy);
+};
+
+}  // namespace webrtc
+
+#endif  // API_VIDEO_CODECS_VP8_FRAME_CONFIG_H_