Refactor + enable GN check on video_coding_utility

webrtc/modules/video_coding/utility/simulcast_rate_allocator.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.
- */
-
-#ifndef WEBRTC_MODULES_VIDEO_CODING_UTILITY_SIMULCAST_RATE_ALLOCATOR_H_
-#define WEBRTC_MODULES_VIDEO_CODING_UTILITY_SIMULCAST_RATE_ALLOCATOR_H_
-
-#include <stdint.h>
-
-#include <map>
-#include <memory>
-
-#include "webrtc/base/constructormagic.h"
-#include "webrtc/common_video/include/video_bitrate_allocator.h"
-#include "webrtc/modules/video_coding/codecs/vp8/temporal_layers.h"
-#include "webrtc/video_encoder.h"
-
-namespace webrtc {
-
-class SimulcastRateAllocator : public VideoBitrateAllocator,
-                               public TemporalLayersListener {
- public:
-  explicit SimulcastRateAllocator(
-      const VideoCodec& codec,
-      std::unique_ptr<TemporalLayersFactory> tl_factory);
-
-  void OnTemporalLayersCreated(int simulcast_id,
-                               TemporalLayers* layers) override;
-
-  BitrateAllocation GetAllocation(uint32_t total_bitrate_bps,
-                                  uint32_t framerate) override;
-  uint32_t GetPreferredBitrateBps(uint32_t framerate) override;
-  const VideoCodec& GetCodec() const;
-
- private:
-  const VideoCodec codec_;
-  std::map<uint32_t, TemporalLayers*> temporal_layers_;
-  std::unique_ptr<TemporalLayersFactory> tl_factory_;
-
-  RTC_DISALLOW_COPY_AND_ASSIGN(SimulcastRateAllocator);
-};
-
-}  // namespace webrtc
-
-#endif  // WEBRTC_MODULES_VIDEO_CODING_UTILITY_SIMULCAST_RATE_ALLOCATOR_H_