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diff --git a/third_party/libwebrtc/api/fec_controller.h b/third_party/libwebrtc/api/fec_controller.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 API_FEC_CONTROLLER_H_
+#define API_FEC_CONTROLLER_H_
+
+#include <memory>
+#include <vector>
+
+#include "api/video/video_frame_type.h"
+#include "modules/include/module_fec_types.h"
+
+namespace webrtc {
+// TODO(yinwa): work in progress. API in class FecController should not be
+// used by other users until this comment is removed.
+
+// Callback class used for telling the user about how to configure the FEC,
+// and the rates sent the last second is returned to the VCM.
+class VCMProtectionCallback {
+ public:
+  virtual int ProtectionRequest(const FecProtectionParams* delta_params,
+                                const FecProtectionParams* key_params,
+                                uint32_t* sent_video_rate_bps,
+                                uint32_t* sent_nack_rate_bps,
+                                uint32_t* sent_fec_rate_bps) = 0;
+
+ protected:
+  virtual ~VCMProtectionCallback() {}
+};
+
+// FecController calculates how much of the allocated network
+// capacity that can be used by an encoder and how much that
+// is needed for redundant packets such as FEC and NACK. It uses an
+// implementation of `VCMProtectionCallback` to set new FEC parameters and get
+// the bitrate currently used for FEC and NACK.
+// Usage:
+// Setup by calling SetProtectionMethod and SetEncodingData.
+// For each encoded image, call UpdateWithEncodedData.
+// Each time the bandwidth estimate change, call UpdateFecRates. UpdateFecRates
+// will return the bitrate that can be used by an encoder.
+// A lock is used to protect internal states, so methods can be called on an
+// arbitrary thread.
+class FecController {
+ public:
+  virtual ~FecController() {}
+
+  virtual void SetProtectionCallback(
+      VCMProtectionCallback* protection_callback) = 0;
+  virtual void SetProtectionMethod(bool enable_fec, bool enable_nack) = 0;
+
+  // Informs loss protectoin logic of initial encoding state.
+  virtual void SetEncodingData(size_t width,
+                               size_t height,
+                               size_t num_temporal_layers,
+                               size_t max_payload_size) = 0;
+
+  // Returns target rate for the encoder given the channel parameters.
+  // Inputs:  estimated_bitrate_bps - the estimated network bitrate in bits/s.
+  //          actual_framerate - encoder frame rate.
+  //          fraction_lost - packet loss rate in % in the network.
+  //          loss_mask_vector - packet loss mask since last time this method
+  //          was called. round_trip_time_ms - round trip time in milliseconds.
+  virtual uint32_t UpdateFecRates(uint32_t estimated_bitrate_bps,
+                                  int actual_framerate,
+                                  uint8_t fraction_lost,
+                                  std::vector<bool> loss_mask_vector,
+                                  int64_t round_trip_time_ms) = 0;
+
+  // Informs of encoded output.
+  virtual void UpdateWithEncodedData(
+      size_t encoded_image_length,
+      VideoFrameType encoded_image_frametype) = 0;
+
+  // Returns whether this FEC Controller needs Loss Vector Mask as input.
+  virtual bool UseLossVectorMask() = 0;
+};
+
+class FecControllerFactoryInterface {
+ public:
+  virtual std::unique_ptr<FecController> CreateFecController() = 0;
+  virtual ~FecControllerFactoryInterface() = default;
+};
+
+}  // namespace webrtc
+#endif  // API_FEC_CONTROLLER_H_