Refactor + enable GN check on video_coding_utility

webrtc/modules/video_coding/utility/qp_parser.h

-/*
- *  Copyright (c) 2015 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_QP_PARSER_H_
-#define WEBRTC_MODULES_VIDEO_CODING_UTILITY_QP_PARSER_H_
-
-#include "webrtc/modules/video_coding/encoded_frame.h"
-
-namespace webrtc {
-
-class QpParser {
- public:
-  QpParser() {}
-  ~QpParser() {}
-
-  // Parses an encoded |frame| and extracts the |qp|.
-  // Returns true on success, false otherwise.
-  bool GetQp(const VCMEncodedFrame& frame, int* qp);
-};
-
-}  // namespace webrtc
-
-#endif  // WEBRTC_MODULES_VIDEO_CODING_UTILITY_QP_PARSER_H_