Update thread annotiation macros to use RTC_ prefix

webrtc/voice_engine/test/auto_test/fakes/conference_transport.h

Index: webrtc/voice_engine/test/auto_test/fakes/conference_transport.h
diff --git a/webrtc/voice_engine/test/auto_test/fakes/conference_transport.h b/webrtc/voice_engine/test/auto_test/fakes/conference_transport.h
index 22711bd5fb9b9c908160fbf5ebedd237d58193a4..a0acd9e4524013d64e512e4a164eb33946dc1b41 100644
--- a/webrtc/voice_engine/test/auto_test/fakes/conference_transport.h
+++ b/webrtc/voice_engine/test/auto_test/fakes/conference_transport.h
@@ -137,8 +137,9 @@ class ConferenceTransport: public webrtc::Transport {
   unsigned int rtt_ms_;
   unsigned int stream_count_;
 
-  std::map<unsigned int, std::pair<int, int>> streams_ GUARDED_BY(stream_crit_);
-  std::deque<Packet> packet_queue_ GUARDED_BY(pq_crit_);
+  std::map<unsigned int, std::pair<int, int>> streams_
+      RTC_GUARDED_BY(stream_crit_);
+  std::deque<Packet> packet_queue_ RTC_GUARDED_BY(pq_crit_);
 
   int local_sender_;  // Channel Id of local sender
   int reflector_;