Bug 1207696 Part 4m - Don't record some threading atomics, r=froydnj.

--HG--
extra : rebase_source : 9e717d9087b4bea7693b0b7fe256740db74389d9

xpcom/threads/nsThreadManager.h

@@ -90,7 +90,9 @@ private:
   RefPtr<nsThread>  mMainThread;
   PRThread*         mMainPRThread;
   mozilla::OffTheBooksMutex mLock;  // protects tables
-  mozilla::Atomic<bool> mInitialized;
+  mozilla::Atomic<bool,
+                  mozilla::SequentiallyConsistent,
+                  mozilla::recordreplay::Behavior::DontPreserve> mInitialized;
 
   // The current number of threads
   uint32_t            mCurrentNumberOfThreads;