Bug 1192194 - Make DOMStorageDBThead::mDBReady atomic. r=smaug

--HG--
extra : rebase_source : d4a9c888ef83efcfddf58c8e447f0f4b440a0c6a

dom/storage/DOMStorageDBThread.h

@@ -10,6 +10,7 @@
 #include "prthread.h"
 #include "prinrval.h"
 #include "nsTArray.h"
+#include "mozilla/Atomics.h"
 #include "mozilla/Monitor.h"
 #include "mozilla/storage/StatementCache.h"
 #include "nsString.h"
@@ -292,7 +293,7 @@ private:
 
   // Whether DB has already been open, avoid races between main thread reads
   // and pending DB init in the background I/O thread
-  bool mDBReady;
+  Atomic<bool, ReleaseAcquire> mDBReady;
 
   // State of the database initiation
   nsresult mStatus;