Revert of I cannot remember what the race here actually was.

include/core/SkPixelRef.h

 /*
  * Copyright 2008 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkPixelRef_DEFINED
 #define SkPixelRef_DEFINED
 
@@ skipping 335 matching lines @@
 private:
     SkBaseMutex*    fMutex; // must remain in scope for the life of this object
 
     // mostly const. fInfo.fAlpahType can be changed at runtime.
     const SkImageInfo fInfo;
 
     // LockRec is only valid if we're in a locked state (isLocked())
     LockRec         fRec;
     int             fLockCount;
 
-    mutable uint32_t fGenerationID;
-    mutable bool     fUniqueGenerationID;
+    mutable SkTRacy<uint32_t> fGenerationID;
+    mutable SkTRacy<bool>     fUniqueGenerationID;
 #ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK
     const uint32_t fStableID;
 #endif
 
     SkTDArray<GenIDChangeListener*> fGenIDChangeListeners;  // pointers are owned
 
     SkString    fURI;
 
     // can go from false to true, but never from true to false
     bool    fIsImmutable;
@@ skipping 18 matching lines @@
     /**
      *  Allocate a new pixelref matching the specified ImageInfo, allocating
      *  the memory for the pixels. If the ImageInfo requires a ColorTable,
      *  the pixelref will ref() the colortable.
      *  On failure return NULL.
      */
     virtual SkPixelRef* create(const SkImageInfo&, size_t rowBytes, SkColorTable*) = 0;
 };
 
 #endif