Move optional.h to webrtc/api/

webrtc/video/overuse_frame_detector.h

 /*
  *  Copyright (c) 2013 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_VIDEO_OVERUSE_FRAME_DETECTOR_H_
 #define WEBRTC_VIDEO_OVERUSE_FRAME_DETECTOR_H_
 
 #include <list>
 #include <memory>
 
+#include "webrtc/api/optional.h"
 #include "webrtc/modules/video_coding/utility/quality_scaler.h"
 #include "webrtc/rtc_base/constructormagic.h"
 #include "webrtc/rtc_base/numerics/exp_filter.h"
-#include "webrtc/rtc_base/optional.h"
 #include "webrtc/rtc_base/sequenced_task_checker.h"
 #include "webrtc/rtc_base/task_queue.h"
 #include "webrtc/rtc_base/thread_annotations.h"
 
 namespace webrtc {
 
 class EncodedFrameObserver;
 class VideoFrame;
 
 struct CpuOveruseOptions {
@@ skipping 123 matching lines @@
   // allocs)?
   const std::unique_ptr<SendProcessingUsage> usage_ GUARDED_BY(task_checker_);
   std::list<FrameTiming> frame_timing_ GUARDED_BY(task_checker_);
 
   RTC_DISALLOW_COPY_AND_ASSIGN(OveruseFrameDetector);
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_VIDEO_OVERUSE_FRAME_DETECTOR_H_