Remove external BitmapImage lazy decoding tracking

Source/platform/graphics/DeferredImageDecoder.h

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 52 matching lines @@
 
     bool isSizeAvailable();
     bool hasColorProfile() const;
     IntSize size() const;
     IntSize frameSizeAtIndex(size_t index) const;
     size_t frameCount();
     int repetitionCount() const;
     size_t clearCacheExceptFrame(size_t);
     bool frameHasAlphaAtIndex(size_t index) const;
     bool frameIsCompleteAtIndex(size_t) const;
-    bool frameIsCachedAndLazyDecodedAtIndex(size_t) const;
     float frameDurationAtIndex(size_t) const;
     size_t frameBytesAtIndex(size_t index) const;
     ImageOrientation orientationAtIndex(size_t index) const;
     bool hotSpot(IntPoint&) const;
 
     // For testing.
     ImageFrameGenerator* frameGenerator() { return m_frameGenerator.get(); }
 
 private:
     explicit DeferredImageDecoder(PassOwnPtr<ImageDecoder> actualDecoder);
@@ skipping 15 matching lines @@
     // Carries only frame state and other information. Does not carry bitmap.
     Vector<FrameData> m_frameData;
     RefPtr<ImageFrameGenerator> m_frameGenerator;
 
     static bool s_enabled;
 };
 
 } // namespace blink
 
 #endif