Update thread annotiation macros in modules to use RTC_ prefix

webrtc/modules/video_coding/generic_decoder.h

 /*
  *  Copyright (c) 2012 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.
  */
 
@@ skipping 51 matching lines @@
   // Protect |_timestampMap|.
   Clock* const _clock;
   // This callback must be set before the decoder thread starts running
   // and must only be unset when external threads (e.g decoder thread)
   // have been stopped. Due to that, the variable should regarded as const
   // while there are more than one threads involved, it must be set
   // from the same thread, and therfore a lock is not required to access it.
   VCMReceiveCallback* _receiveCallback = nullptr;
   VCMTiming* _timing;
   rtc::CriticalSection lock_;
-  VCMTimestampMap _timestampMap GUARDED_BY(lock_);
+  VCMTimestampMap _timestampMap RTC_GUARDED_BY(lock_);
   uint64_t _lastReceivedPictureID;
   int64_t ntp_offset_;
 };
 
 class VCMGenericDecoder {
  public:
   explicit VCMGenericDecoder(VideoDecoder* decoder, bool isExternal = false);
   ~VCMGenericDecoder();
 
   /**
@@ skipping 25 matching lines @@
   uint32_t _nextFrameInfoIdx;
   std::unique_ptr<VideoDecoder> decoder_;
   VideoCodecType _codecType;
   const bool _isExternal;
   VideoContentType _last_keyframe_content_type;
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_VIDEO_CODING_GENERIC_DECODER_H_