Update thread annotiation macros in rtc_base to use RTC_ prefix

webrtc/rtc_base/asyncinvoker.h

 /*
  *  Copyright 2014 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 230 matching lines @@
         posted_from, callback_posted_from, thread_, functor, callback,
         callback_host, id);
     return true;
   }
 
  private:
   // Callback when |thread_| is destroyed.
   void ThreadDestroyed();
 
   CriticalSection crit_;
-  Thread* thread_ GUARDED_BY(crit_);
-  AsyncInvoker invoker_ GUARDED_BY(crit_);
+  Thread* thread_ RTC_GUARDED_BY(crit_);
+  AsyncInvoker invoker_ RTC_GUARDED_BY(crit_);
 };
 
 }  // namespace rtc
 
 #endif  // WEBRTC_RTC_BASE_ASYNCINVOKER_H_