diff --git a/include/core/SkColorFilter.h b/include/core/SkColorFilter.h
index 2a886bc..f875ab4 100644
--- a/include/core/SkColorFilter.h
+++ b/include/core/SkColorFilter.h
@@ -147,7 +147,7 @@
 
 protected:
     SkFilterShader(SkFlattenableReadBuffer& );
-    virtual void flatten(SkFlattenableWriteBuffer& ) SK_OVERRIDE;
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
 private:
     SkShader*       fShader;
diff --git a/include/core/SkColorShader.h b/include/core/SkColorShader.h
index 356e87a..e64a183 100644
--- a/include/core/SkColorShader.h
+++ b/include/core/SkColorShader.h
@@ -53,7 +53,7 @@
 
 protected:
     SkColorShader(SkFlattenableReadBuffer&);
-    virtual void flatten(SkFlattenableWriteBuffer&) SK_OVERRIDE;
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
 private:
 
diff --git a/include/core/SkComposeShader.h b/include/core/SkComposeShader.h
index 2fc1239..77729d9 100644
--- a/include/core/SkComposeShader.h
+++ b/include/core/SkComposeShader.h
@@ -44,7 +44,7 @@
 
 protected:
     SkComposeShader(SkFlattenableReadBuffer& );
-    virtual void flatten(SkFlattenableWriteBuffer& );
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
 private:
 
diff --git a/include/core/SkEmptyShader.h b/include/core/SkEmptyShader.h
index 53e3d2b..13da457 100644
--- a/include/core/SkEmptyShader.h
+++ b/include/core/SkEmptyShader.h
@@ -33,8 +33,7 @@
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkEmptyShader)
 
 protected:
-    SkEmptyShader(SkFlattenableReadBuffer&);
-    virtual void flatten(SkFlattenableWriteBuffer&) SK_OVERRIDE;
+    SkEmptyShader(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {}
 
 private:
     typedef SkShader INHERITED;
diff --git a/include/core/SkFlattenable.h b/include/core/SkFlattenable.h
index 554ffc0..ba1495f 100644
--- a/include/core/SkFlattenable.h
+++ b/include/core/SkFlattenable.h
@@ -75,11 +75,6 @@
      override of flatten().
      */
     virtual Factory getFactory() = 0;
-    /** Override this to write data specific to your subclass into the buffer,
-     being sure to call your super-class' version first. This data will later
-     be passed to your Factory function, returned by getFactory().
-     */
-    virtual void flatten(SkFlattenableWriteBuffer&);
     
     static Factory NameToFactory(const char name[]);
     static const char* FactoryToName(Factory);
@@ -94,6 +89,11 @@
 
 protected:
     SkFlattenable(SkFlattenableReadBuffer&) {}
+    /** Override this to write data specific to your subclass into the buffer,
+     being sure to call your super-class' version first. This data will later
+     be passed to your Factory function, returned by getFactory().
+     */
+    virtual void flatten(SkFlattenableWriteBuffer&) const;
 
 private:
 #if !SK_ALLOW_STATIC_GLOBAL_INITIALIZERS
@@ -101,6 +101,7 @@
 #endif
 
     friend class SkGraphics;
+    friend class SkFlattenableWriteBuffer;
 };
 
 // helpers for matrix and region
diff --git a/include/core/SkMallocPixelRef.h b/include/core/SkMallocPixelRef.h
index cdfec75..802e2b2 100644
--- a/include/core/SkMallocPixelRef.h
+++ b/include/core/SkMallocPixelRef.h
@@ -28,8 +28,6 @@
     size_t getSize() const { return fSize; }
     void* getAddr() const { return fStorage; }
 
-    // overrides from SkPixelRef
-    virtual void flatten(SkFlattenableWriteBuffer&);
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkMallocPixelRef)
 
 protected:
@@ -38,6 +36,7 @@
     virtual void onUnlockPixels();
 
     SkMallocPixelRef(SkFlattenableReadBuffer& buffer);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
 private:
     void*           fStorage;
diff --git a/include/core/SkMaskFilter.h b/include/core/SkMaskFilter.h
index 2808de7..12de01b 100644
--- a/include/core/SkMaskFilter.h
+++ b/include/core/SkMaskFilter.h
@@ -55,8 +55,6 @@
     virtual bool filterMask(SkMask* dst, const SkMask& src, const SkMatrix&,
                             SkIPoint* margin);
 
-    virtual void flatten(SkFlattenableWriteBuffer& ) {}
-
     enum BlurType {
         kNone_BlurType,    //!< this maskfilter is not a blur
         kNormal_BlurType,  //!< fuzzy inside and outside
@@ -94,7 +92,7 @@
 
 protected:
     // empty for now, but lets get our subclass to remember to init us for the future
-    SkMaskFilter(SkFlattenableReadBuffer&) {}
+    SkMaskFilter(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {}
 
 private:
     friend class SkDraw;
@@ -106,6 +104,8 @@
      */
     bool filterPath(const SkPath& devPath, const SkMatrix& devMatrix,
                     const SkRasterClip&, SkBounder*, SkBlitter* blitter);
+
+    typedef SkFlattenable INHERITED;
 };
 
 #endif
diff --git a/include/core/SkPaint.h b/include/core/SkPaint.h
index 4d4fbc6..d660ff3 100644
--- a/include/core/SkPaint.h
+++ b/include/core/SkPaint.h
@@ -941,16 +941,16 @@
     // overrides
     virtual bool filterPath(SkPath* dst, const SkPath& src, SkScalar* width);
 
-    // overrides for SkFlattenable
-    virtual void flatten(SkFlattenableWriteBuffer&);
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkStrokePathEffect)
 
+protected:
+    SkStrokePathEffect(SkFlattenableReadBuffer&);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
+
 private:
     SkScalar    fWidth, fMiter;
     uint8_t     fStyle, fJoin, fCap;
 
-    SkStrokePathEffect(SkFlattenableReadBuffer&);
-
     typedef SkPathEffect INHERITED;
 
     // illegal
diff --git a/include/core/SkPathEffect.h b/include/core/SkPathEffect.h
index 48181ee..b160f8f 100644
--- a/include/core/SkPathEffect.h
+++ b/include/core/SkPathEffect.h
@@ -58,7 +58,8 @@
 
 protected:
     SkPairPathEffect(SkFlattenableReadBuffer&);
-    virtual void flatten(SkFlattenableWriteBuffer&) SK_OVERRIDE;
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
+
     // these are visible to our subclasses
     SkPathEffect* fPE0, *fPE1;
     
@@ -87,9 +88,10 @@
 
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkComposePathEffect)
 
-private:
+protected:
     SkComposePathEffect(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {}
 
+private:
     // illegal
     SkComposePathEffect(const SkComposePathEffect&);
     SkComposePathEffect& operator=(const SkComposePathEffect&);
@@ -117,9 +119,10 @@
 
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkSumPathEffect)
 
-private:
+protected:
     SkSumPathEffect(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {}
 
+private:
     // illegal
     SkSumPathEffect(const SkSumPathEffect&);
     SkSumPathEffect& operator=(const SkSumPathEffect&);
diff --git a/include/core/SkPixelRef.h b/include/core/SkPixelRef.h
index d84c285..c902765 100644
--- a/include/core/SkPixelRef.h
+++ b/include/core/SkPixelRef.h
@@ -122,9 +122,6 @@
         support deep copies.  */
     virtual SkPixelRef* deepCopy(SkBitmap::Config config) { return NULL; }
 
-    // serialization
-    virtual void flatten(SkFlattenableWriteBuffer&);
-
 #ifdef SK_BUILD_FOR_ANDROID
     /**
      *  Acquire a "global" ref on this object.
@@ -168,7 +165,9 @@
     */
     SkBaseMutex* mutex() const { return fMutex; }
 
+    // serialization
     SkPixelRef(SkFlattenableReadBuffer&, SkBaseMutex*);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
 private:
 
diff --git a/include/core/SkRasterizer.h b/include/core/SkRasterizer.h
index d249898..923028f 100644
--- a/include/core/SkRasterizer.h
+++ b/include/core/SkRasterizer.h
@@ -28,9 +28,8 @@
                    const SkIRect* clipBounds, SkMaskFilter* filter,
                    SkMask* mask, SkMask::CreateMode mode);
 
-    virtual void flatten(SkFlattenableWriteBuffer& ) SK_OVERRIDE {}
 protected:
-    SkRasterizer(SkFlattenableReadBuffer&);
+    SkRasterizer(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {}
 
     virtual bool onRasterize(const SkPath& path, const SkMatrix& matrix,
                              const SkIRect* clipBounds,
diff --git a/include/core/SkShader.h b/include/core/SkShader.h
index 331799a..72bd784 100644
--- a/include/core/SkShader.h
+++ b/include/core/SkShader.h
@@ -293,7 +293,6 @@
     static SkShader* CreateBitmapShader(const SkBitmap& src,
                                         TileMode tmx, TileMode tmy);
 
-    virtual void flatten(SkFlattenableWriteBuffer& ) SK_OVERRIDE;
 protected:
     enum MatrixClass {
         kLinear_MatrixClass,            // no perspective
@@ -309,6 +308,7 @@
     MatrixClass         getInverseClass() const { return (MatrixClass)fTotalInverseClass; }
 
     SkShader(SkFlattenableReadBuffer& );
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 private:
     SkMatrix*           fLocalMatrix;
     SkMatrix            fTotalInverse;
diff --git a/include/core/SkShape.h b/include/core/SkShape.h
index 3968fce..0196156 100644
--- a/include/core/SkShape.h
+++ b/include/core/SkShape.h
@@ -31,8 +31,6 @@
      */
     void drawMatrix(SkCanvas*, const SkMatrix&);
 
-    // overrides
-    virtual void flatten(SkFlattenableWriteBuffer&);
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkShape)
 
 protected:
diff --git a/include/core/SkXfermode.h b/include/core/SkXfermode.h
index 65e0f0d..86bafea 100644
--- a/include/core/SkXfermode.h
+++ b/include/core/SkXfermode.h
@@ -214,12 +214,11 @@
     virtual void xferA8(SkAlpha dst[], const SkPMColor src[], int count,
                         const SkAlpha aa[]) SK_OVERRIDE;
 
-    // overrides from SkFlattenable
-    virtual void    flatten(SkFlattenableWriteBuffer&) SK_OVERRIDE;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkProcXfermode)
 
 protected:
     SkProcXfermode(SkFlattenableReadBuffer&);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
     // allow subclasses to update this after we unflatten
     void setProc(SkXfermodeProc proc) {
diff --git a/include/effects/Sk1DPathEffect.h b/include/effects/Sk1DPathEffect.h
index 53126f2..25b6ff3 100644
--- a/include/effects/Sk1DPathEffect.h
+++ b/include/effects/Sk1DPathEffect.h
@@ -63,12 +63,11 @@
 
 protected:
     SkPath1DPathEffect(SkFlattenableReadBuffer& buffer);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
     // overrides from Sk1DPathEffect
     virtual SkScalar begin(SkScalar contourLength) SK_OVERRIDE;
     virtual SkScalar next(SkPath*, SkScalar distance, SkPathMeasure&) SK_OVERRIDE;
-    // overrides from SkFlattenable
-    virtual void flatten(SkFlattenableWriteBuffer&) SK_OVERRIDE;
     
 private:
     SkPath      fPath;          // copied from constructor
diff --git a/include/effects/Sk2DPathEffect.h b/include/effects/Sk2DPathEffect.h
index 28c5aea..67e7857 100644
--- a/include/effects/Sk2DPathEffect.h
+++ b/include/effects/Sk2DPathEffect.h
@@ -21,8 +21,6 @@
     // overrides
     virtual bool filterPath(SkPath*, const SkPath&, SkScalar* width) SK_OVERRIDE;
 
-    // overrides from SkFlattenable
-    virtual void flatten(SkFlattenableWriteBuffer&) SK_OVERRIDE;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(Sk2DPathEffect)
 
 protected:
@@ -46,6 +44,7 @@
 
     // protected so that subclasses can call this during unflattening
     Sk2DPathEffect(SkFlattenableReadBuffer&);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
 private:
     SkMatrix    fMatrix, fInverse;
@@ -69,8 +68,8 @@
 
 protected:
     SkPath2DPathEffect(SkFlattenableReadBuffer& buffer);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
-    virtual void flatten(SkFlattenableWriteBuffer&) SK_OVERRIDE;
     virtual void next(const SkPoint&, int u, int v, SkPath* dst) SK_OVERRIDE;
 
 private:
diff --git a/include/effects/SkAvoidXfermode.h b/include/effects/SkAvoidXfermode.h
index db14f25..298ce5b 100644
--- a/include/effects/SkAvoidXfermode.h
+++ b/include/effects/SkAvoidXfermode.h
@@ -51,12 +51,11 @@
     virtual void xferA8(SkAlpha dst[], const SkPMColor src[], int count,
                         const SkAlpha aa[]) SK_OVERRIDE;
 
-    // overrides from SkFlattenable
-    virtual void flatten(SkFlattenableWriteBuffer&) SK_OVERRIDE;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkAvoidXfermode)
 
 protected:
     SkAvoidXfermode(SkFlattenableReadBuffer&);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
 private:
     SkColor     fOpColor;
diff --git a/include/effects/SkBlurDrawLooper.h b/include/effects/SkBlurDrawLooper.h
index 453a618..2aff2f3 100644
--- a/include/effects/SkBlurDrawLooper.h
+++ b/include/effects/SkBlurDrawLooper.h
@@ -48,8 +48,7 @@
 
 protected:
     SkBlurDrawLooper(SkFlattenableReadBuffer&);
-    // overrides from SkFlattenable
-    virtual void flatten(SkFlattenableWriteBuffer& );
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
 private:
     SkMaskFilter*   fBlur;
diff --git a/include/effects/SkBlurImageFilter.h b/include/effects/SkBlurImageFilter.h
index 846b900..bf5173d 100644
--- a/include/effects/SkBlurImageFilter.h
+++ b/include/effects/SkBlurImageFilter.h
@@ -21,10 +21,10 @@
 
 protected:
     explicit SkBlurImageFilter(SkFlattenableReadBuffer& buffer);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
     virtual bool onFilterImage(Proxy*, const SkBitmap& src, const SkMatrix&,
                                SkBitmap* result, SkIPoint* offset) SK_OVERRIDE;
-    virtual void flatten(SkFlattenableWriteBuffer& buffer) SK_OVERRIDE;
 
 private:
     SkSize   fSigma;
diff --git a/include/effects/SkColorMatrixFilter.h b/include/effects/SkColorMatrixFilter.h
index abfd95d..1ac6fbf 100644
--- a/include/effects/SkColorMatrixFilter.h
+++ b/include/effects/SkColorMatrixFilter.h
@@ -28,9 +28,6 @@
     virtual uint32_t getFlags() SK_OVERRIDE;
     virtual bool asColorMatrix(SkScalar matrix[20]) SK_OVERRIDE;
 
-    // overrides for SkFlattenable
-    virtual void flatten(SkFlattenableWriteBuffer& buffer) SK_OVERRIDE;
-
     struct State {
         int32_t fArray[20];
         int     fShift;
@@ -41,6 +38,7 @@
 
 protected:
     SkColorMatrixFilter(SkFlattenableReadBuffer& buffer);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
 private:
 
diff --git a/include/effects/SkCornerPathEffect.h b/include/effects/SkCornerPathEffect.h
index 8c58476..01dae7e 100644
--- a/include/effects/SkCornerPathEffect.h
+++ b/include/effects/SkCornerPathEffect.h
@@ -29,13 +29,11 @@
     //  This method is not exported to java.
     virtual bool filterPath(SkPath* dst, const SkPath& src, SkScalar* width);
 
-    // overrides for SkFlattenable
-    //  This method is not exported to java.
-    virtual void flatten(SkFlattenableWriteBuffer&);
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkCornerPathEffect)
 
 protected:
     SkCornerPathEffect(SkFlattenableReadBuffer&);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
 private:
     SkScalar    fRadius;
diff --git a/include/effects/SkDashPathEffect.h b/include/effects/SkDashPathEffect.h
index 29a6d1b..300edcd 100644
--- a/include/effects/SkDashPathEffect.h
+++ b/include/effects/SkDashPathEffect.h
@@ -34,13 +34,11 @@
     // overrides for SkFlattenable
     //  This method is not exported to java.
     virtual Factory getFactory();
-    //  This method is not exported to java.
-    virtual void flatten(SkFlattenableWriteBuffer&);
-
     static SkFlattenable* CreateProc(SkFlattenableReadBuffer&);
 
 protected:
     SkDashPathEffect(SkFlattenableReadBuffer&);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
     
 private:
     SkScalar*   fIntervals;
diff --git a/include/effects/SkDiscretePathEffect.h b/include/effects/SkDiscretePathEffect.h
index 76a3523..30d07d3 100644
--- a/include/effects/SkDiscretePathEffect.h
+++ b/include/effects/SkDiscretePathEffect.h
@@ -28,13 +28,11 @@
     //  This method is not exported to java.
     virtual bool filterPath(SkPath* dst, const SkPath& src, SkScalar* width);
 
-    // overrides for SkFlattenable
-    //  This method is not exported to java.
-    virtual void flatten(SkFlattenableWriteBuffer&);
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkDiscretePathEffect)
 
 protected:
     SkDiscretePathEffect(SkFlattenableReadBuffer&);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
 private:
     SkScalar fSegLength, fPerterb;
diff --git a/include/effects/SkEmbossMaskFilter.h b/include/effects/SkEmbossMaskFilter.h
index a03a283..24815a5 100644
--- a/include/effects/SkEmbossMaskFilter.h
+++ b/include/effects/SkEmbossMaskFilter.h
@@ -34,14 +34,11 @@
     virtual bool filterMask(SkMask* dst, const SkMask& src, const SkMatrix&,
                             SkIPoint* margin);
 
-    // overrides from SkFlattenable
-    //  This method is not exported to java.
-    virtual void flatten(SkFlattenableWriteBuffer&);
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkEmbossMaskFilter)
 
-
 protected:
     SkEmbossMaskFilter(SkFlattenableReadBuffer&);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
 private:
     Light       fLight;
diff --git a/include/effects/SkGroupShape.h b/include/effects/SkGroupShape.h
index 56e9d32..ac0d994 100644
--- a/include/effects/SkGroupShape.h
+++ b/include/effects/SkGroupShape.h
@@ -131,9 +131,6 @@
      */
     void removeAllShapes();
 
-    // overrides
-    virtual void flatten(SkFlattenableWriteBuffer&);
-
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkGroupShape)
 
 protected:
@@ -141,6 +138,7 @@
     virtual void onDraw(SkCanvas*);
 
     SkGroupShape(SkFlattenableReadBuffer&);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
 private:
     struct Rec {
diff --git a/include/effects/SkKernel33MaskFilter.h b/include/effects/SkKernel33MaskFilter.h
index 9c43629..bd47320 100644
--- a/include/effects/SkKernel33MaskFilter.h
+++ b/include/effects/SkKernel33MaskFilter.h
@@ -23,11 +23,9 @@
     virtual SkMask::Format getFormat();
     virtual bool filterMask(SkMask*, const SkMask&, const SkMatrix&, SkIPoint*);
 
-    // overrides from SkFlattenable
-    virtual void flatten(SkFlattenableWriteBuffer& wb);
-
 protected:
     SkKernel33ProcMaskFilter(SkFlattenableReadBuffer& rb);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
 private:
     int fPercent256;
@@ -48,8 +46,6 @@
     // override from SkKernel33ProcMaskFilter
     virtual uint8_t computeValue(uint8_t* const* srcRows);
     
-    // overrides from SkFlattenable
-    virtual void flatten(SkFlattenableWriteBuffer& wb);
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkKernel33MaskFilter)
     
 private:
@@ -57,6 +53,7 @@
     int fShift;
 
     SkKernel33MaskFilter(SkFlattenableReadBuffer& rb);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
     
     typedef SkKernel33ProcMaskFilter INHERITED;
 };
diff --git a/include/effects/SkLayerDrawLooper.h b/include/effects/SkLayerDrawLooper.h
index 3e7306f..0bc4af2 100644
--- a/include/effects/SkLayerDrawLooper.h
+++ b/include/effects/SkLayerDrawLooper.h
@@ -105,9 +105,7 @@
     
 protected:
     SkLayerDrawLooper(SkFlattenableReadBuffer&);
-
-    // overrides from SkFlattenable
-    virtual void flatten(SkFlattenableWriteBuffer& );
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
     
 private:
     struct Rec {
diff --git a/include/effects/SkLayerRasterizer.h b/include/effects/SkLayerRasterizer.h
index e31ed33..c51b174 100644
--- a/include/effects/SkLayerRasterizer.h
+++ b/include/effects/SkLayerRasterizer.h
@@ -32,13 +32,11 @@
 	*/
     void addLayer(const SkPaint& paint, SkScalar dx, SkScalar dy);
 
-    // overrides from SkFlattenable
-    virtual void    flatten(SkFlattenableWriteBuffer&);
-
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkLayerRasterizer)
 
 protected:
     SkLayerRasterizer(SkFlattenableReadBuffer&);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
     // override from SkRasterizer
     virtual bool onRasterize(const SkPath& path, const SkMatrix& matrix,
diff --git a/include/effects/SkMorphologyImageFilter.h b/include/effects/SkMorphologyImageFilter.h
index 368d17b..5450576 100644
--- a/include/effects/SkMorphologyImageFilter.h
+++ b/include/effects/SkMorphologyImageFilter.h
@@ -13,11 +13,12 @@
 
 class SK_API SkMorphologyImageFilter : public SkImageFilter {
 public:
-    explicit SkMorphologyImageFilter(SkFlattenableReadBuffer& buffer);
     SkMorphologyImageFilter(int radiusX, int radiusY);
 
 protected:
-    virtual void flatten(SkFlattenableWriteBuffer& buffer) SK_OVERRIDE;
+    SkMorphologyImageFilter(SkFlattenableReadBuffer& buffer);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
+
     SkISize    radius() const { return fRadius; }
 
 private:
@@ -28,7 +29,6 @@
 class SK_API SkDilateImageFilter : public SkMorphologyImageFilter {
 public:
     SkDilateImageFilter(int radiusX, int radiusY) : INHERITED(radiusX, radiusY) {}
-    explicit SkDilateImageFilter(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {}
 
     virtual bool asADilate(SkISize* radius) const SK_OVERRIDE;
     virtual bool onFilterImage(Proxy*, const SkBitmap& src, const SkMatrix&,
@@ -36,13 +36,16 @@
 
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkDilateImageFilter)
 
+protected:
+    SkDilateImageFilter(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {}
+
+private:
     typedef SkMorphologyImageFilter INHERITED;
 };
 
 class SK_API SkErodeImageFilter : public SkMorphologyImageFilter {
 public:
     SkErodeImageFilter(int radiusX, int radiusY) : INHERITED(radiusX, radiusY) {}
-    explicit SkErodeImageFilter(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {}
 
     virtual bool asAnErode(SkISize* radius) const SK_OVERRIDE;
     virtual bool onFilterImage(Proxy*, const SkBitmap& src, const SkMatrix&,
@@ -50,6 +53,9 @@
 
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkErodeImageFilter)
 
+protected:
+    SkErodeImageFilter(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {}
+
 private:
     typedef SkMorphologyImageFilter INHERITED;
 };
diff --git a/include/effects/SkPixelXorXfermode.h b/include/effects/SkPixelXorXfermode.h
index fe0536d..e991108 100644
--- a/include/effects/SkPixelXorXfermode.h
+++ b/include/effects/SkPixelXorXfermode.h
@@ -21,20 +21,18 @@
 public:
     SkPixelXorXfermode(SkColor opColor) : fOpColor(opColor) {}
 
-    // override from SkFlattenable
-    virtual void flatten(SkFlattenableWriteBuffer&);
-
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkPixelXorXfermode)
 
 protected:
+    SkPixelXorXfermode(SkFlattenableReadBuffer& rb);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
+
     // override from SkXfermode
     virtual SkPMColor xferColor(SkPMColor src, SkPMColor dst);
 
 private:
     SkColor fOpColor;
 
-    SkPixelXorXfermode(SkFlattenableReadBuffer& rb);
-
     typedef SkXfermode INHERITED;
 };
 
diff --git a/include/effects/SkRectShape.h b/include/effects/SkRectShape.h
index b0efc28..a06adfc 100644
--- a/include/effects/SkRectShape.h
+++ b/include/effects/SkRectShape.h
@@ -19,11 +19,9 @@
     SkPaint& paint() { return fPaint; }
     const SkPaint& paint() const { return fPaint; }
 
-    // overrides
-    virtual void flatten(SkFlattenableWriteBuffer&);
-    
 protected:
     SkPaintShape(SkFlattenableReadBuffer& buffer);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
     
 private:
     SkPaint fPaint;
@@ -40,13 +38,11 @@
     void setCircle(SkScalar x, SkScalar y, SkScalar radius);
     void setRRect(const SkRect&, SkScalar rx, SkScalar ry);
 
-    // overrides
-    virtual void flatten(SkFlattenableWriteBuffer&);
-
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkRectShape)
 
 protected:
     SkRectShape(SkFlattenableReadBuffer&);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
     // overrides
     virtual void onDraw(SkCanvas*);
diff --git a/include/effects/SkTableMaskFilter.h b/include/effects/SkTableMaskFilter.h
index 15bb930..e2472d7 100644
--- a/include/effects/SkTableMaskFilter.h
+++ b/include/effects/SkTableMaskFilter.h
@@ -51,12 +51,11 @@
     virtual SkMask::Format getFormat();
     virtual bool filterMask(SkMask*, const SkMask&, const SkMatrix&, SkIPoint*);
     
-    // overrides from SkFlattenable
-    virtual void flatten(SkFlattenableWriteBuffer& wb);
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkTableMaskFilter)
 
 protected:
     SkTableMaskFilter(SkFlattenableReadBuffer& rb);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
 private:
     uint8_t fTable[256];
diff --git a/include/effects/SkTestImageFilters.h b/include/effects/SkTestImageFilters.h
index e2c9cf4..a28ed8b 100755
--- a/include/effects/SkTestImageFilters.h
+++ b/include/effects/SkTestImageFilters.h
@@ -15,12 +15,11 @@
 
 protected:
     SkOffsetImageFilter(SkFlattenableReadBuffer& buffer);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
     virtual bool onFilterImage(Proxy*, const SkBitmap& src, const SkMatrix&,
                                SkBitmap* result, SkIPoint* loc) SK_OVERRIDE;
     virtual bool onFilterBounds(const SkIRect&, const SkMatrix&, SkIRect*) SK_OVERRIDE;
-    // overrides from SkFlattenable
-    virtual void flatten(SkFlattenableWriteBuffer&) SK_OVERRIDE;
 
 private:
     SkVector fOffset;
@@ -42,12 +41,11 @@
     
 protected:
     SkComposeImageFilter(SkFlattenableReadBuffer& buffer);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
     
     virtual bool onFilterImage(Proxy*, const SkBitmap& src, const SkMatrix&,
                                SkBitmap* result, SkIPoint* loc) SK_OVERRIDE;
     virtual bool onFilterBounds(const SkIRect&, const SkMatrix&, SkIRect*) SK_OVERRIDE;
-    // overrides from SkFlattenable
-    virtual void flatten(SkFlattenableWriteBuffer&) SK_OVERRIDE;
     
 private:
     SkImageFilter*  fOuter;
@@ -70,12 +68,11 @@
     
 protected:
     SkMergeImageFilter(SkFlattenableReadBuffer& buffer);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
     
     virtual bool onFilterImage(Proxy*, const SkBitmap& src, const SkMatrix&,
                                SkBitmap* result, SkIPoint* loc) SK_OVERRIDE;
     virtual bool onFilterBounds(const SkIRect&, const SkMatrix&, SkIRect*) SK_OVERRIDE;
-    // overrides from SkFlattenable
-    virtual void flatten(SkFlattenableWriteBuffer&) SK_OVERRIDE;
     
 private:
     SkImageFilter**     fFilters;
@@ -103,11 +100,10 @@
     
 protected:
     SkColorFilterImageFilter(SkFlattenableReadBuffer& buffer);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
     
     virtual bool onFilterImage(Proxy*, const SkBitmap& src, const SkMatrix&,
                                SkBitmap* result, SkIPoint* loc) SK_OVERRIDE;
-    // overrides from SkFlattenable
-    virtual void flatten(SkFlattenableWriteBuffer&) SK_OVERRIDE;
     
 private:
     SkColorFilter*  fColorFilter;
@@ -126,11 +122,10 @@
     
 protected:
     SkDownSampleImageFilter(SkFlattenableReadBuffer& buffer);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
     
     virtual bool onFilterImage(Proxy*, const SkBitmap& src, const SkMatrix&,
                                SkBitmap* result, SkIPoint* loc) SK_OVERRIDE;
-    // overrides from SkFlattenable
-    virtual void flatten(SkFlattenableWriteBuffer&) SK_OVERRIDE;
     
 private:
     SkScalar fScale;
diff --git a/include/effects/SkTransparentShader.h b/include/effects/SkTransparentShader.h
index 0aa9192..531da74 100644
--- a/include/effects/SkTransparentShader.h
+++ b/include/effects/SkTransparentShader.h
@@ -23,8 +23,6 @@
     virtual void    shadeSpan(int x, int y, SkPMColor[], int count) SK_OVERRIDE;
     virtual void    shadeSpan16(int x, int y, uint16_t span[], int count) SK_OVERRIDE;
 
-    // overrides for SkFlattenable
-    virtual void flatten(SkFlattenableWriteBuffer&) SK_OVERRIDE;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkTransparentShader)
 
 private:
diff --git a/include/images/SkFlipPixelRef.h b/include/images/SkFlipPixelRef.h
index c9ba026..3d5c097 100644
--- a/include/images/SkFlipPixelRef.h
+++ b/include/images/SkFlipPixelRef.h
@@ -33,7 +33,6 @@
     const SkRegion& beginUpdate(SkBitmap* device);
     void endUpdate();
 
-    virtual void flatten(SkFlattenableWriteBuffer&);
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkFlipPixelRef)
 
 protected:
@@ -41,6 +40,7 @@
     virtual void onUnlockPixels();
 
     SkFlipPixelRef(SkFlattenableReadBuffer&);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
     
 private:
     void getFrontBack(const void** front, void** back) const {
diff --git a/include/images/SkImageRef.h b/include/images/SkImageRef.h
index 8fc4754..bec3527 100644
--- a/include/images/SkImageRef.h
+++ b/include/images/SkImageRef.h
@@ -60,9 +60,6 @@
     // returns the factory parameter
     SkImageDecoderFactory* setDecoderFactory(SkImageDecoderFactory*);
 
-    // overrides
-    virtual void flatten(SkFlattenableWriteBuffer&);
-
 protected:
     /** Override if you want to install a custom allocator.
         When this is called we will have already acquired the mutex!
@@ -79,6 +76,7 @@
     virtual void onUnlockPixels();
     
     SkImageRef(SkFlattenableReadBuffer&);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
     SkBitmap fBitmap;
 
diff --git a/include/utils/SkUnitMappers.h b/include/utils/SkUnitMappers.h
index d8856ae..901650d 100644
--- a/include/utils/SkUnitMappers.h
+++ b/include/utils/SkUnitMappers.h
@@ -24,8 +24,7 @@
 
 protected:
     SkDiscreteMapper(SkFlattenableReadBuffer& );
-    // overrides from SkFlattenable
-    virtual void flatten(SkFlattenableWriteBuffer& );
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
 private:
     int     fSegments;
diff --git a/samplecode/ClockFaceView.cpp b/samplecode/ClockFaceView.cpp
index fe7bb90..9827545 100644
--- a/samplecode/ClockFaceView.cpp
+++ b/samplecode/ClockFaceView.cpp
@@ -70,13 +70,6 @@
                     SkTDArray<SkPoint>* pts)
     : Sk2DPathEffect(matrix), fRadius(radius), fPts(pts) {}
 
-    virtual void flatten(SkFlattenableWriteBuffer& buffer)
-    {
-        this->INHERITED::flatten(buffer);
-
-        buffer.writeScalar(fRadius);
-    }
-
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(Dot2DPathEffect)
 
 protected:
@@ -95,11 +88,16 @@
         dst->addCircle(loc.fX, loc.fY, fRadius);
     }
 
-    Dot2DPathEffect(SkFlattenableReadBuffer& buffer) : Sk2DPathEffect(buffer)
+    Dot2DPathEffect(SkFlattenableReadBuffer& buffer) : INHERITED(buffer)
     {
         fRadius = buffer.readScalar();
         fPts = NULL;
     }
+    virtual void flatten(SkFlattenableWriteBuffer& buffer) const SK_OVERRIDE {
+        this->INHERITED::flatten(buffer);
+        buffer.writeScalar(fRadius);
+    }
+
 private:
     SkScalar fRadius;
     SkTDArray<SkPoint>* fPts;
diff --git a/samplecode/SampleAll.cpp b/samplecode/SampleAll.cpp
index 8d2157f..5b12e68 100644
--- a/samplecode/SampleAll.cpp
+++ b/samplecode/SampleAll.cpp
@@ -159,11 +159,6 @@
     Dot2DPathEffect(SkScalar radius, const SkMatrix& matrix)
         : Sk2DPathEffect(matrix), fRadius(radius) {}
 
-    virtual void flatten(SkFlattenableWriteBuffer& buffer) {
-        this->INHERITED::flatten(buffer);
-        
-        buffer.writeScalar(fRadius);
-    }
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(Dot2DPathEffect)
 
 protected:
@@ -171,9 +166,14 @@
         dst->addCircle(loc.fX, loc.fY, fRadius);
     }
     
-    Dot2DPathEffect(SkFlattenableReadBuffer& buffer) : Sk2DPathEffect(buffer) {
+    Dot2DPathEffect(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {
         fRadius = buffer.readScalar();
     }
+    virtual void flatten(SkFlattenableWriteBuffer& buffer) const SK_OVERRIDE {
+        this->INHERITED::flatten(buffer);
+        buffer.writeScalar(fRadius);
+    }
+
 private:
     SkScalar fRadius;
 
@@ -218,11 +218,6 @@
         return false;
     }
     
-    virtual void flatten(SkFlattenableWriteBuffer& buffer) {
-        this->INHERITED::flatten(buffer);
-        buffer.writeScalar(fWidth);
-    }
-
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(Line2DPathEffect)
 
 protected:
@@ -241,10 +236,14 @@
         }
     }
     
-    Line2DPathEffect(SkFlattenableReadBuffer& buffer) : Sk2DPathEffect(buffer) {
+    Line2DPathEffect(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {
         fWidth = buffer.readScalar();
     }
-    
+    virtual void flatten(SkFlattenableWriteBuffer& buffer) const SK_OVERRIDE {
+        this->INHERITED::flatten(buffer);
+        buffer.writeScalar(fWidth);
+    }
+
 private:
     SkScalar fWidth;
 
diff --git a/samplecode/SampleSlides.cpp b/samplecode/SampleSlides.cpp
index 3c656e9..5251036 100644
--- a/samplecode/SampleSlides.cpp
+++ b/samplecode/SampleSlides.cpp
@@ -612,12 +612,6 @@
         return false;
     }
     
-    virtual void flatten(SkFlattenableWriteBuffer& buffer)
-    {
-        this->INHERITED::flatten(buffer);
-        buffer.writeScalar(fWidth);
-    }
-
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(Line2DPathEffect)
 protected:
 	virtual void nextSpan(int u, int v, int ucount, SkPath* dst)
@@ -637,10 +631,15 @@
         }
     }
     
-    Line2DPathEffect(SkFlattenableReadBuffer& buffer) : Sk2DPathEffect(buffer)
+    Line2DPathEffect(SkFlattenableReadBuffer& buffer) : INHERITED(buffer)
     {
         fWidth = buffer.readScalar();
     }
+    virtual void flatten(SkFlattenableWriteBuffer& buffer) const SK_OVERRIDE
+    {
+        this->INHERITED::flatten(buffer);
+        buffer.writeScalar(fWidth);
+    }
     
 private:
     SkScalar fWidth;
diff --git a/samplecode/SampleText.cpp b/samplecode/SampleText.cpp
index 7ce1abe..7ed16dc 100644
--- a/samplecode/SampleText.cpp
+++ b/samplecode/SampleText.cpp
@@ -131,11 +131,6 @@
 
     typedef SkFlattenable* (*Factory)(SkFlattenableReadBuffer&);
 
-    // overrides for SkFlattenable
-    virtual void flatten(SkFlattenableWriteBuffer& b) {
-    //    this->INHERITED::flatten(b);  How can we know if this is legal????
-        b.write32(SkScalarToFixed(fExp));
-    }
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkPowerMode)
 
 private:
@@ -143,10 +138,14 @@
     uint8_t fTable[256];    // cache
 
     void init(SkScalar exponent);
-    SkPowerMode(SkFlattenableReadBuffer& b) : SkXfermode(b) {
+    SkPowerMode(SkFlattenableReadBuffer& b) : INHERITED(b) {
         // read the exponent
         this->init(SkFixedToScalar(b.readS32()));
     }
+    virtual void flatten(SkFlattenableWriteBuffer& b) const SK_OVERRIDE {
+        this->INHERITED::flatten(b);
+        b.write32(SkScalarToFixed(fExp));
+    }
 
     typedef SkXfermode INHERITED;
 };
diff --git a/samplecode/SampleTextEffects.cpp b/samplecode/SampleTextEffects.cpp
index e6bca82..a37d103 100644
--- a/samplecode/SampleTextEffects.cpp
+++ b/samplecode/SampleTextEffects.cpp
@@ -189,10 +189,6 @@
         return false;
     }
 
-    virtual void flatten(SkFlattenableWriteBuffer& buffer) {
-        this->INHERITED::flatten(buffer);
-        buffer.writeScalar(fWidth);
-    }
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(Line2DPathEffect)
 
 protected:
@@ -211,9 +207,13 @@
         }
     }
 
-    Line2DPathEffect(SkFlattenableReadBuffer& buffer) : Sk2DPathEffect(buffer) {
+    Line2DPathEffect(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {
         fWidth = buffer.readScalar();
     }
+    virtual void flatten(SkFlattenableWriteBuffer& buffer) const SK_OVERRIDE {
+        this->INHERITED::flatten(buffer);
+        buffer.writeScalar(fWidth);
+    }
 
 private:
     SkScalar fWidth;
diff --git a/src/animator/SkDrawExtraPathEffect.cpp b/src/animator/SkDrawExtraPathEffect.cpp
index c901df3..c9de254 100644
--- a/src/animator/SkDrawExtraPathEffect.cpp
+++ b/src/animator/SkDrawExtraPathEffect.cpp
@@ -140,8 +140,6 @@
     }
 
 private:
-    virtual void flatten(SkFlattenableWriteBuffer& ) {}
-
     static bool GetContourLength(const char* token, size_t len, void* clen, SkScriptValue* value) {
         if (SK_LITERAL_STR_EQUAL("contourLength", token, len)) {
             value->fOperand.fScalar = *(SkScalar*) clen;
diff --git a/src/core/SkBitmapProcShader.cpp b/src/core/SkBitmapProcShader.cpp
index e3c46d0..7ae6afc 100644
--- a/src/core/SkBitmapProcShader.cpp
+++ b/src/core/SkBitmapProcShader.cpp
@@ -68,7 +68,7 @@
     return kDefault_BitmapType;
 }
 
-void SkBitmapProcShader::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkBitmapProcShader::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
 
     fRawBitmap.flatten(buffer);
diff --git a/src/core/SkBitmapProcShader.h b/src/core/SkBitmapProcShader.h
index 6140259..26b4cc2 100644
--- a/src/core/SkBitmapProcShader.h
+++ b/src/core/SkBitmapProcShader.h
@@ -36,7 +36,7 @@
 
 protected:
     SkBitmapProcShader(SkFlattenableReadBuffer& );
-    virtual void flatten(SkFlattenableWriteBuffer& );
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
     SkBitmap          fRawBitmap;   // experimental for RLE encoding
     SkBitmapProcState fState;
diff --git a/src/core/SkBlitter.cpp b/src/core/SkBlitter.cpp
index 2ce0197..735ad04 100644
--- a/src/core/SkBlitter.cpp
+++ b/src/core/SkBlitter.cpp
@@ -659,14 +659,13 @@
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(Sk3DShader)
 
 protected:
-    Sk3DShader(SkFlattenableReadBuffer& buffer) :
-            INHERITED(buffer) {
+    Sk3DShader(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {
         fProxy = static_cast<SkShader*>(buffer.readFlattenable());
         fPMColor = buffer.readU32();
         fMask = NULL;
     }
 
-    virtual void flatten(SkFlattenableWriteBuffer& buffer) {
+    virtual void flatten(SkFlattenableWriteBuffer& buffer) const SK_OVERRIDE {
         this->INHERITED::flatten(buffer);
         buffer.writeFlattenable(fProxy);
         buffer.write32(fPMColor);
diff --git a/src/core/SkColorFilter.cpp b/src/core/SkColorFilter.cpp
index 2ca88bb..b96b77e 100644
--- a/src/core/SkColorFilter.cpp
+++ b/src/core/SkColorFilter.cpp
@@ -66,7 +66,7 @@
     this->INHERITED::endSession();
 }
 
-void SkFilterShader::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkFilterShader::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     buffer.writeFlattenable(fShader);
     buffer.writeFlattenable(fFilter);
diff --git a/src/core/SkComposeShader.cpp b/src/core/SkComposeShader.cpp
index c8d3299..6f3eccd 100644
--- a/src/core/SkComposeShader.cpp
+++ b/src/core/SkComposeShader.cpp
@@ -70,7 +70,7 @@
     uint8_t     fAlpha;
 };
 
-void SkComposeShader::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkComposeShader::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     buffer.writeFlattenable(fShaderA);
     buffer.writeFlattenable(fShaderB);
diff --git a/src/core/SkFlattenable.cpp b/src/core/SkFlattenable.cpp
index 9d8c215..6a445ea 100644
--- a/src/core/SkFlattenable.cpp
+++ b/src/core/SkFlattenable.cpp
@@ -37,7 +37,7 @@
 
 ///////////////////////////////////////////////////////////////////////////////
 
-void SkFlattenable::flatten(SkFlattenableWriteBuffer&)
+void SkFlattenable::flatten(SkFlattenableWriteBuffer&) const
 {
     /*  we don't write anything at the moment, but this allows our subclasses
         to not know that, since we want them to always call INHERITED::flatten()
diff --git a/src/core/SkMallocPixelRef.cpp b/src/core/SkMallocPixelRef.cpp
index 1cf64a1..313a26e 100644
--- a/src/core/SkMallocPixelRef.cpp
+++ b/src/core/SkMallocPixelRef.cpp
@@ -34,7 +34,7 @@
     // nothing to do
 }
 
-void SkMallocPixelRef::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkMallocPixelRef::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
 
     buffer.write32(fSize);
diff --git a/src/core/SkPathEffect.cpp b/src/core/SkPathEffect.cpp
index 0c0143d..bbf6f18 100644
--- a/src/core/SkPathEffect.cpp
+++ b/src/core/SkPathEffect.cpp
@@ -29,7 +29,8 @@
 /*
     Format: [oe0-factory][pe1-factory][pe0-size][pe0-data][pe1-data]
 */
-void SkPairPathEffect::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkPairPathEffect::flatten(SkFlattenableWriteBuffer& buffer) const {
+    this->INHERITED::flatten(buffer);
     buffer.writeFlattenable(fPE0);
     buffer.writeFlattenable(fPE1);
 }
@@ -108,7 +109,8 @@
     return true;
 }
 
-void SkStrokePathEffect::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkStrokePathEffect::flatten(SkFlattenableWriteBuffer& buffer) const {
+    this->INHERITED::flatten(buffer);
     buffer.writeScalar(fWidth);
     buffer.writeScalar(fMiter);
     buffer.write8(fStyle);
diff --git a/src/core/SkPixelRef.cpp b/src/core/SkPixelRef.cpp
index 2d4daae..f01fbea 100644
--- a/src/core/SkPixelRef.cpp
+++ b/src/core/SkPixelRef.cpp
@@ -49,7 +49,7 @@
     fIsImmutable = buffer.readBool();
 }
 
-void SkPixelRef::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkPixelRef::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     buffer.writeBool(fIsImmutable);
 }
diff --git a/src/core/SkRasterizer.cpp b/src/core/SkRasterizer.cpp
index 7ccced8..d5023b3 100644
--- a/src/core/SkRasterizer.cpp
+++ b/src/core/SkRasterizer.cpp
@@ -12,9 +12,6 @@
 #include "SkMaskFilter.h"
 #include "SkPath.h"
 
-// do nothing for now, since we don't store anything at flatten time
-SkRasterizer::SkRasterizer(SkFlattenableReadBuffer&) {}
-
 bool SkRasterizer::rasterize(const SkPath& fillPath, const SkMatrix& matrix,
                              const SkIRect* clipBounds, SkMaskFilter* filter,
                              SkMask* mask, SkMask::CreateMode mode) {
diff --git a/src/core/SkShader.cpp b/src/core/SkShader.cpp
index a3b3b6a..bfdebc1 100644
--- a/src/core/SkShader.cpp
+++ b/src/core/SkShader.cpp
@@ -41,7 +41,7 @@
     SkDEBUGCODE(fInSession = false;)
 }
 
-void SkShader::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkShader::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     buffer.writeBool(fLocalMatrix != NULL);
     if (fLocalMatrix) {
@@ -238,7 +238,7 @@
     fColor = b.readU32();
 }
 
-void SkColorShader::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkColorShader::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     buffer.write8(fInheritColor);
     if (fInheritColor) {
@@ -331,8 +331,6 @@
 
 #include "SkEmptyShader.h"
 
-SkEmptyShader::SkEmptyShader(SkFlattenableReadBuffer& b) : INHERITED(b) {}
-
 uint32_t SkEmptyShader::getFlags() { return 0; }
 uint8_t SkEmptyShader::getSpan16Alpha() const { return 0; }
 
@@ -351,8 +349,4 @@
     SkDEBUGFAIL("should never get called, since setContext() returned false");
 }
 
-void SkEmptyShader::flatten(SkFlattenableWriteBuffer& buffer) {
-    this->INHERITED::flatten(buffer);
-}
-
 SK_DEFINE_FLATTENABLE_REGISTRAR(SkEmptyShader)
diff --git a/src/core/SkShape.cpp b/src/core/SkShape.cpp
index 0c4907e..c386af8 100644
--- a/src/core/SkShape.cpp
+++ b/src/core/SkShape.cpp
@@ -60,10 +60,6 @@
     inc_shape(this);
 }
 
-void SkShape::flatten(SkFlattenableWriteBuffer& buffer) {
-    this->INHERITED::flatten(buffer);
-}
-
 void SkShape::onDraw(SkCanvas*) {}
 
 SK_DEFINE_FLATTENABLE_REGISTRAR(SkShape)
diff --git a/src/core/SkXfermode.cpp b/src/core/SkXfermode.cpp
index bcb721d..62e62a1 100644
--- a/src/core/SkXfermode.cpp
+++ b/src/core/SkXfermode.cpp
@@ -685,7 +685,8 @@
     fProc = (SkXfermodeProc)buffer.readFunctionPtr();
 }
 
-void SkProcXfermode::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkProcXfermode::flatten(SkFlattenableWriteBuffer& buffer) const {
+    this->INHERITED::flatten(buffer);
     if (buffer.isCrossProcess()) {
         // function pointer is only valid in the current process. Write a NULL
         // so it can't be accidentally used
@@ -729,16 +730,10 @@
         return true;
     }
 
-    virtual void flatten(SkFlattenableWriteBuffer& buffer) {
-        this->INHERITED::flatten(buffer);
-        buffer.write32(fMode);
-    }
-
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkProcCoeffXfermode)
 
 protected:
-    SkProcCoeffXfermode(SkFlattenableReadBuffer& buffer)
-            : INHERITED(buffer) {
+    SkProcCoeffXfermode(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {
         fMode = (SkXfermode::Mode)buffer.readU32();
 
         const ProcCoeff& rec = gProcCoeffs[fMode];
@@ -749,6 +744,11 @@
         this->INHERITED::setProc(rec.fProc);
     }
 
+    virtual void flatten(SkFlattenableWriteBuffer& buffer) const SK_OVERRIDE {
+        this->INHERITED::flatten(buffer);
+        buffer.write32(fMode);
+    }
+
 private:
     Mode    fMode;
     Coeff   fSrcCoeff, fDstCoeff;
diff --git a/src/effects/Sk1DPathEffect.cpp b/src/effects/Sk1DPathEffect.cpp
index 11170f4..62ca7b3 100644
--- a/src/effects/Sk1DPathEffect.cpp
+++ b/src/effects/Sk1DPathEffect.cpp
@@ -156,7 +156,8 @@
     return fInitialOffset;
 }
 
-void SkPath1DPathEffect::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkPath1DPathEffect::flatten(SkFlattenableWriteBuffer& buffer) const {
+    this->INHERITED::flatten(buffer);
     buffer.writeScalar(fAdvance);
     if (fAdvance > 0) {
         fPath.flatten(buffer);
diff --git a/src/effects/Sk2DPathEffect.cpp b/src/effects/Sk2DPathEffect.cpp
index 60ec257..9a92162 100644
--- a/src/effects/Sk2DPathEffect.cpp
+++ b/src/effects/Sk2DPathEffect.cpp
@@ -64,7 +64,8 @@
 
 ///////////////////////////////////////////////////////////////////////////////
 
-void Sk2DPathEffect::flatten(SkFlattenableWriteBuffer& buffer) {
+void Sk2DPathEffect::flatten(SkFlattenableWriteBuffer& buffer) const {
+    this->INHERITED::flatten(buffer);
     char storage[SkMatrix::kMaxFlattenSize];
     uint32_t size = fMatrix.flatten(storage);
     buffer.write32(size);
@@ -92,7 +93,7 @@
     fPath.unflatten(buffer);
 }
 
-void SkPath2DPathEffect::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkPath2DPathEffect::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     fPath.flatten(buffer);
 }
diff --git a/src/effects/SkAvoidXfermode.cpp b/src/effects/SkAvoidXfermode.cpp
index d668222..b5375e6 100644
--- a/src/effects/SkAvoidXfermode.cpp
+++ b/src/effects/SkAvoidXfermode.cpp
@@ -29,7 +29,7 @@
     fMode = (Mode)buffer.readU8();
 }
 
-void SkAvoidXfermode::flatten(SkFlattenableWriteBuffer& buffer)
+void SkAvoidXfermode::flatten(SkFlattenableWriteBuffer& buffer) const
 {
     this->INHERITED::flatten(buffer);
 
diff --git a/src/effects/SkBlurDrawLooper.cpp b/src/effects/SkBlurDrawLooper.cpp
index 656f8f7..3b78573 100644
--- a/src/effects/SkBlurDrawLooper.cpp
+++ b/src/effects/SkBlurDrawLooper.cpp
@@ -61,7 +61,8 @@
     SkSafeUnref(fColorFilter);
 }
 
-void SkBlurDrawLooper::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkBlurDrawLooper::flatten(SkFlattenableWriteBuffer& buffer) const {
+    this->INHERITED::flatten(buffer);
     buffer.writeScalar(fDx);
     buffer.writeScalar(fDy);
     buffer.write32(fBlurColor);
diff --git a/src/effects/SkBlurImageFilter.cpp b/src/effects/SkBlurImageFilter.cpp
index 1446e92..522f4b0 100644
--- a/src/effects/SkBlurImageFilter.cpp
+++ b/src/effects/SkBlurImageFilter.cpp
@@ -24,7 +24,7 @@
     return true;
 }
 
-void SkBlurImageFilter::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkBlurImageFilter::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     buffer.writeScalar(fSigma.fWidth);
     buffer.writeScalar(fSigma.fHeight);
diff --git a/src/effects/SkBlurMaskFilter.cpp b/src/effects/SkBlurMaskFilter.cpp
index eb64000..306770b 100644
--- a/src/effects/SkBlurMaskFilter.cpp
+++ b/src/effects/SkBlurMaskFilter.cpp
@@ -24,9 +24,6 @@
     virtual BlurType asABlur(BlurInfo*) const SK_OVERRIDE;
     virtual void computeFastBounds(const SkRect& src, SkRect* dst) SK_OVERRIDE;
 
-    // overrides from SkFlattenable
-    virtual void flatten(SkFlattenableWriteBuffer&) SK_OVERRIDE;
-
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkBlurMaskFilterImpl)
 
 private:
@@ -35,6 +32,7 @@
     uint32_t                    fBlurFlags;
 
     SkBlurMaskFilterImpl(SkFlattenableReadBuffer&);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
     
     typedef SkMaskFilter INHERITED;
 };
@@ -112,7 +110,7 @@
     SkASSERT((unsigned)fBlurStyle < SkBlurMaskFilter::kBlurStyleCount);
 }
 
-void SkBlurMaskFilterImpl::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkBlurMaskFilterImpl::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     buffer.writeScalar(fRadius);
     buffer.write32(fBlurStyle);
diff --git a/src/effects/SkColorFilters.cpp b/src/effects/SkColorFilters.cpp
index 2970c7c..3b97250 100644
--- a/src/effects/SkColorFilters.cpp
+++ b/src/effects/SkColorFilters.cpp
@@ -50,7 +50,7 @@
     bool isModeValid() const { return ILLEGAL_XFERMODE_MODE != fMode; }
 
 protected:
-    virtual void flatten(SkFlattenableWriteBuffer& buffer) {
+    virtual void flatten(SkFlattenableWriteBuffer& buffer) const SK_OVERRIDE {
         this->INHERITED::flatten(buffer);
         buffer.write32(fColor);
         buffer.write32(fMode);
@@ -193,7 +193,7 @@
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(Proc_SkModeColorFilter)
 
 protected:
-    virtual void flatten(SkFlattenableWriteBuffer& buffer) {
+    virtual void flatten(SkFlattenableWriteBuffer& buffer) const SK_OVERRIDE {
         this->INHERITED::flatten(buffer);
         buffer.writeFunctionPtr((void*)fProc);
         buffer.writeFunctionPtr((void*)fProc16);
@@ -312,7 +312,7 @@
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkLightingColorFilter)
 
 protected:
-    virtual void flatten(SkFlattenableWriteBuffer& buffer) {
+    virtual void flatten(SkFlattenableWriteBuffer& buffer) const SK_OVERRIDE {
         this->INHERITED::flatten(buffer);
         buffer.write32(fMul);
         buffer.write32(fAdd);
@@ -489,7 +489,7 @@
         }
     }
 
-    virtual void flatten(SkFlattenableWriteBuffer& buffer) {}
+    virtual void flatten(SkFlattenableWriteBuffer& buffer) const SK_OVERRIDE {}
 
     virtual Factory getFactory() {
         return CreateProc;
diff --git a/src/effects/SkColorMatrixFilter.cpp b/src/effects/SkColorMatrixFilter.cpp
index 47ff8ad..c688625 100644
--- a/src/effects/SkColorMatrixFilter.cpp
+++ b/src/effects/SkColorMatrixFilter.cpp
@@ -310,7 +310,7 @@
 
 ///////////////////////////////////////////////////////////////////////////////
 
-void SkColorMatrixFilter::flatten(SkFlattenableWriteBuffer& buffer)  {
+void SkColorMatrixFilter::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
 
     buffer.writeFunctionPtr((void*)fProc);
diff --git a/src/effects/SkCornerPathEffect.cpp b/src/effects/SkCornerPathEffect.cpp
index 5eb94a4..bf59a27 100644
--- a/src/effects/SkCornerPathEffect.cpp
+++ b/src/effects/SkCornerPathEffect.cpp
@@ -129,7 +129,8 @@
     return true;
 }
 
-void SkCornerPathEffect::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkCornerPathEffect::flatten(SkFlattenableWriteBuffer& buffer) const {
+    this->INHERITED::flatten(buffer);
     buffer.writeScalar(fRadius);
 }
 
diff --git a/src/effects/SkDashPathEffect.cpp b/src/effects/SkDashPathEffect.cpp
index 7950d64..88f003b 100644
--- a/src/effects/SkDashPathEffect.cpp
+++ b/src/effects/SkDashPathEffect.cpp
@@ -140,9 +140,10 @@
     return fInitialDashLength < 0 ? NULL : CreateProc;
 }
 
-void SkDashPathEffect::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkDashPathEffect::flatten(SkFlattenableWriteBuffer& buffer) const {
     SkASSERT(fInitialDashLength >= 0);
 
+    this->INHERITED::flatten(buffer);
     buffer.write32(fCount);
     buffer.write32(fInitialDashIndex);
     buffer.writeScalar(fInitialDashLength);
diff --git a/src/effects/SkDiscretePathEffect.cpp b/src/effects/SkDiscretePathEffect.cpp
index 089bed6..e8c0ec9 100644
--- a/src/effects/SkDiscretePathEffect.cpp
+++ b/src/effects/SkDiscretePathEffect.cpp
@@ -67,7 +67,8 @@
     return true;
 }
 
-void SkDiscretePathEffect::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkDiscretePathEffect::flatten(SkFlattenableWriteBuffer& buffer) const {
+    this->INHERITED::flatten(buffer);
     buffer.writeScalar(fSegLength);
     buffer.writeScalar(fPerterb);
 }
diff --git a/src/effects/SkEmbossMaskFilter.cpp b/src/effects/SkEmbossMaskFilter.cpp
index 26a5e2e..245ccd6 100644
--- a/src/effects/SkEmbossMaskFilter.cpp
+++ b/src/effects/SkEmbossMaskFilter.cpp
@@ -122,11 +122,12 @@
     fBlurRadius = buffer.readScalar();
 }
 
-void SkEmbossMaskFilter::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkEmbossMaskFilter::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
 
-    fLight.fPad = 0;    // for the font-cache lookup to be clean
-    buffer.writeMul4(&fLight, sizeof(fLight));
+    Light tmpLight = fLight;
+    tmpLight.fPad = 0;    // for the font-cache lookup to be clean
+    buffer.writeMul4(&tmpLight, sizeof(tmpLight));
     buffer.writeScalar(fBlurRadius);
 }
 
diff --git a/src/effects/SkGradientShader.cpp b/src/effects/SkGradientShader.cpp
index 0fcb514..a93bd52 100644
--- a/src/effects/SkGradientShader.cpp
+++ b/src/effects/SkGradientShader.cpp
@@ -174,6 +174,8 @@
 
 protected:
     Gradient_Shader(SkFlattenableReadBuffer& );
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
+
     SkUnitMapper* fMapper;
     SkMatrix    fPtsToUnit;     // set by subclass
     SkMatrix    fDstToIndex;
@@ -190,7 +192,6 @@
     };
     Rec*        fRecs;
 
-    virtual void flatten(SkFlattenableWriteBuffer& );
     const uint16_t*     getCache16() const;
     const SkPMColor*    getCache32() const;
 
@@ -404,7 +405,7 @@
     fColorsAreOpaque = colorAlpha == 0xFF;
 }
 
-void Gradient_Shader::flatten(SkFlattenableWriteBuffer& buffer) {
+void Gradient_Shader::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     buffer.writeFlattenable(fMapper);
     buffer.write32(fColorCount);
@@ -849,7 +850,15 @@
                              SkScalar* twoPointRadialParams) const SK_OVERRIDE;
     virtual GradientType asAGradient(GradientInfo* info) const SK_OVERRIDE;
 
-    virtual void flatten(SkFlattenableWriteBuffer& buffer) SK_OVERRIDE {
+    SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(Linear_Gradient)
+
+protected:
+    Linear_Gradient(SkFlattenableReadBuffer& buffer)
+        : INHERITED(buffer),
+          fStart(unflatten_point(buffer)),
+          fEnd(unflatten_point(buffer)) {
+    }
+    virtual void flatten(SkFlattenableWriteBuffer& buffer)  const SK_OVERRIDE {
         this->INHERITED::flatten(buffer);
         buffer.writeScalar(fStart.fX);
         buffer.writeScalar(fStart.fY);
@@ -857,15 +866,6 @@
         buffer.writeScalar(fEnd.fY);
     }
 
-    SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(Linear_Gradient)
-
-protected:
-    Linear_Gradient(SkFlattenableReadBuffer& buffer)
-        : Gradient_Shader(buffer),
-          fStart(unflatten_point(buffer)),
-          fEnd(unflatten_point(buffer)) {
-    }
-
 private:
     typedef Gradient_Shader INHERITED;
     const SkPoint fStart;
@@ -1507,21 +1507,20 @@
         return kRadial_GradientType;
     }
 
-    virtual void flatten(SkFlattenableWriteBuffer& buffer) SK_OVERRIDE {
-        this->INHERITED::flatten(buffer);
-        buffer.writeScalar(fCenter.fX);
-        buffer.writeScalar(fCenter.fY);
-        buffer.writeScalar(fRadius);
-    }
-
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(Radial_Gradient)
 
 protected:
     Radial_Gradient(SkFlattenableReadBuffer& buffer)
-        : Gradient_Shader(buffer),
+        : INHERITED(buffer),
           fCenter(unflatten_point(buffer)),
           fRadius(buffer.readScalar()) {
     }
+    virtual void flatten(SkFlattenableWriteBuffer& buffer) const SK_OVERRIDE {
+        this->INHERITED::flatten(buffer);
+        buffer.writeScalar(fCenter.fX);
+        buffer.writeScalar(fCenter.fY);
+        buffer.writeScalar(fRadius);
+    }
 
 private:
     typedef Gradient_Shader INHERITED;
@@ -2039,7 +2038,19 @@
         return true;
     }
 
-    virtual void flatten(SkFlattenableWriteBuffer& buffer) SK_OVERRIDE {
+    SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(Two_Point_Radial_Gradient)
+
+protected:
+    Two_Point_Radial_Gradient(SkFlattenableReadBuffer& buffer)
+            : INHERITED(buffer),
+              fCenter1(unflatten_point(buffer)),
+              fCenter2(unflatten_point(buffer)),
+              fRadius1(buffer.readScalar()),
+              fRadius2(buffer.readScalar()) {
+        init();
+    };
+
+    virtual void flatten(SkFlattenableWriteBuffer& buffer) const SK_OVERRIDE {
         this->INHERITED::flatten(buffer);
         buffer.writeScalar(fCenter1.fX);
         buffer.writeScalar(fCenter1.fY);
@@ -2049,18 +2060,6 @@
         buffer.writeScalar(fRadius2);
     }
 
-    SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(Two_Point_Radial_Gradient)
-
-protected:
-    Two_Point_Radial_Gradient(SkFlattenableReadBuffer& buffer)
-            : Gradient_Shader(buffer),
-              fCenter1(unflatten_point(buffer)),
-              fCenter2(unflatten_point(buffer)),
-              fRadius1(buffer.readScalar()),
-              fRadius2(buffer.readScalar()) {
-        init();
-    };
-
 private:
     typedef Gradient_Shader INHERITED;
     const SkPoint fCenter1;
@@ -2125,19 +2124,18 @@
         return kSweep_GradientType;
     }
 
-    virtual void flatten(SkFlattenableWriteBuffer& buffer) SK_OVERRIDE {
-        this->INHERITED::flatten(buffer);
-        buffer.writeScalar(fCenter.fX);
-        buffer.writeScalar(fCenter.fY);
-    }
-
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(Sweep_Gradient)
 
 protected:
     Sweep_Gradient(SkFlattenableReadBuffer& buffer)
-        : Gradient_Shader(buffer),
+        : INHERITED(buffer),
           fCenter(unflatten_point(buffer)) {
     }
+    virtual void flatten(SkFlattenableWriteBuffer& buffer) const SK_OVERRIDE {
+        this->INHERITED::flatten(buffer);
+        buffer.writeScalar(fCenter.fX);
+        buffer.writeScalar(fCenter.fY);
+    }
 
 private:
     typedef Gradient_Shader INHERITED;
diff --git a/src/effects/SkGroupShape.cpp b/src/effects/SkGroupShape.cpp
index b27026e..83a2043 100644
--- a/src/effects/SkGroupShape.cpp
+++ b/src/effects/SkGroupShape.cpp
@@ -83,7 +83,7 @@
     }
 }
 
-void SkGroupShape::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkGroupShape::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
 
     int count = fList.count();
diff --git a/src/effects/SkKernel33MaskFilter.cpp b/src/effects/SkKernel33MaskFilter.cpp
index f01451c..10aabc4 100644
--- a/src/effects/SkKernel33MaskFilter.cpp
+++ b/src/effects/SkKernel33MaskFilter.cpp
@@ -73,7 +73,7 @@
     return true;
 }
 
-void SkKernel33ProcMaskFilter::flatten(SkFlattenableWriteBuffer& wb) {
+void SkKernel33ProcMaskFilter::flatten(SkFlattenableWriteBuffer& wb) const {
     this->INHERITED::flatten(wb);
     wb.write32(fPercent256);
 }
@@ -104,7 +104,7 @@
     return (uint8_t)value;
 }
 
-void SkKernel33MaskFilter::flatten(SkFlattenableWriteBuffer& wb) {
+void SkKernel33MaskFilter::flatten(SkFlattenableWriteBuffer& wb) const {
     this->INHERITED::flatten(wb);
     wb.writeMul4(fKernel, 9 * sizeof(int));
     wb.write32(fShift);
diff --git a/src/effects/SkLayerDrawLooper.cpp b/src/effects/SkLayerDrawLooper.cpp
index acb3e88..250306c 100644
--- a/src/effects/SkLayerDrawLooper.cpp
+++ b/src/effects/SkLayerDrawLooper.cpp
@@ -180,7 +180,7 @@
 
 ///////////////////////////////////////////////////////////////////////////////
 
-void SkLayerDrawLooper::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkLayerDrawLooper::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
 
 #ifdef SK_DEBUG
diff --git a/src/effects/SkLayerRasterizer.cpp b/src/effects/SkLayerRasterizer.cpp
index ae4eb2e..81263d1 100644
--- a/src/effects/SkLayerRasterizer.cpp
+++ b/src/effects/SkLayerRasterizer.cpp
@@ -197,7 +197,7 @@
     }
 }
 
-void SkLayerRasterizer::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkLayerRasterizer::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
 
     buffer.write32(fLayers.count());
diff --git a/src/effects/SkMorphologyImageFilter.cpp b/src/effects/SkMorphologyImageFilter.cpp
index 78fabc5..09610cd 100644
--- a/src/effects/SkMorphologyImageFilter.cpp
+++ b/src/effects/SkMorphologyImageFilter.cpp
@@ -19,7 +19,7 @@
 }
 
 
-void SkMorphologyImageFilter::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkMorphologyImageFilter::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     buffer.writeScalar(fRadius.fWidth);
     buffer.writeScalar(fRadius.fHeight);
diff --git a/src/effects/SkPixelXorXfermode.cpp b/src/effects/SkPixelXorXfermode.cpp
index b4bbaf9..7b58ed7 100644
--- a/src/effects/SkPixelXorXfermode.cpp
+++ b/src/effects/SkPixelXorXfermode.cpp
@@ -18,13 +18,13 @@
     return res;
 }
 
-void SkPixelXorXfermode::flatten(SkFlattenableWriteBuffer& wb) {
+void SkPixelXorXfermode::flatten(SkFlattenableWriteBuffer& wb) const {
     this->INHERITED::flatten(wb);
     wb.write32(fOpColor);
 }
 
 SkPixelXorXfermode::SkPixelXorXfermode(SkFlattenableReadBuffer& rb)
-        : SkXfermode(rb) {
+        : INHERITED(rb) {
     fOpColor = rb.readU32();
 }
 
diff --git a/src/effects/SkRectShape.cpp b/src/effects/SkRectShape.cpp
index d7e2628..68d1e1f 100644
--- a/src/effects/SkRectShape.cpp
+++ b/src/effects/SkRectShape.cpp
@@ -60,7 +60,7 @@
     }
 }
 
-void SkRectShape::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkRectShape::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
 
     buffer.writeRect(fBounds);
@@ -74,7 +74,7 @@
 
 ///////////////////////////////////////////////////////////////////////////////
 
-void SkPaintShape::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkPaintShape::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     
     fPaint.flatten(buffer);
diff --git a/src/effects/SkTableColorFilter.cpp b/src/effects/SkTableColorFilter.cpp
index 8b60326..c709dd4 100644
--- a/src/effects/SkTableColorFilter.cpp
+++ b/src/effects/SkTableColorFilter.cpp
@@ -35,12 +35,12 @@
 
     virtual void filterSpan(const SkPMColor src[], int count,
                             SkPMColor dst[]) SK_OVERRIDE;
-    virtual void flatten(SkFlattenableWriteBuffer&) SK_OVERRIDE;
 
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkTable_ColorFilter)
 
 protected:
     SkTable_ColorFilter(SkFlattenableReadBuffer& buffer);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
 private:
     SkBitmap* fBitmap;
@@ -145,7 +145,7 @@
 
 #include "SkPackBits.h"
 
-void SkTable_ColorFilter::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkTable_ColorFilter::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
 
     uint8_t storage[5*256];
diff --git a/src/effects/SkTableMaskFilter.cpp b/src/effects/SkTableMaskFilter.cpp
index 3a3d0e5..fed0c5d 100644
--- a/src/effects/SkTableMaskFilter.cpp
+++ b/src/effects/SkTableMaskFilter.cpp
@@ -71,7 +71,7 @@
     return SkMask::kA8_Format;
 }
 
-void SkTableMaskFilter::flatten(SkFlattenableWriteBuffer& wb) {
+void SkTableMaskFilter::flatten(SkFlattenableWriteBuffer& wb) const {
     this->INHERITED::flatten(wb);
     wb.writePad(fTable, 256);
 }
diff --git a/src/effects/SkTestImageFilters.cpp b/src/effects/SkTestImageFilters.cpp
index 688e298..0dd360b 100755
--- a/src/effects/SkTestImageFilters.cpp
+++ b/src/effects/SkTestImageFilters.cpp
@@ -32,7 +32,7 @@
     return true;
 }
 
-void SkOffsetImageFilter::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkOffsetImageFilter::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     buffer.writeScalar(fOffset.x());
     buffer.writeScalar(fOffset.y());
@@ -84,7 +84,7 @@
            fOuter->filterBounds(tmp, ctm, dst);
 }
 
-void SkComposeImageFilter::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkComposeImageFilter::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
 
     buffer.writeFlattenable(fOuter);
@@ -238,7 +238,7 @@
     return true;
 }
 
-void SkMergeImageFilter::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkMergeImageFilter::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
 
     int storedCount = fCount;
@@ -307,7 +307,7 @@
     return true;
 }
 
-void SkColorFilterImageFilter::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkColorFilterImageFilter::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     
     buffer.writeFlattenable(fColorFilter);
@@ -369,7 +369,7 @@
     return true;
 }
 
-void SkDownSampleImageFilter::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkDownSampleImageFilter::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     
     buffer.writeScalar(fScale);
diff --git a/src/effects/SkTransparentShader.cpp b/src/effects/SkTransparentShader.cpp
index c827c11..28b075f 100644
--- a/src/effects/SkTransparentShader.cpp
+++ b/src/effects/SkTransparentShader.cpp
@@ -125,8 +125,3 @@
         memcpy(span, src, count << 1);
     }
 }
-
-void SkTransparentShader::flatten(SkFlattenableWriteBuffer& buffer) {
-    this->INHERITED::flatten(buffer);
-}
-
diff --git a/src/images/SkFlipPixelRef.cpp b/src/images/SkFlipPixelRef.cpp
index 768a67d..6ab5bbc 100644
--- a/src/images/SkFlipPixelRef.cpp
+++ b/src/images/SkFlipPixelRef.cpp
@@ -60,7 +60,7 @@
     fMutex.release();
 }
 
-void SkFlipPixelRef::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkFlipPixelRef::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     
     buffer.write32(fSize);
diff --git a/src/images/SkImageRef.cpp b/src/images/SkImageRef.cpp
index cdd80e7..1d6b270 100644
--- a/src/images/SkImageRef.cpp
+++ b/src/images/SkImageRef.cpp
@@ -189,7 +189,7 @@
     fFactory = NULL;
 }
 
-void SkImageRef::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkImageRef::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
 
     buffer.write8(fConfig);
diff --git a/src/ports/SkImageRef_ashmem.cpp b/src/ports/SkImageRef_ashmem.cpp
index a9208e8..f1fb829 100644
--- a/src/ports/SkImageRef_ashmem.cpp
+++ b/src/ports/SkImageRef_ashmem.cpp
@@ -210,7 +210,7 @@
     fBitmap.setPixels(NULL, NULL);
 }
 
-void SkImageRef_ashmem::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkImageRef_ashmem::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     const char* uri = getURI();
     if (uri) {
diff --git a/src/ports/SkImageRef_ashmem.h b/src/ports/SkImageRef_ashmem.h
index 38442f6..5b4e814 100644
--- a/src/ports/SkImageRef_ashmem.h
+++ b/src/ports/SkImageRef_ashmem.h
@@ -22,11 +22,12 @@
     SkImageRef_ashmem(SkStream*, SkBitmap::Config, int sampleSize = 1);
     virtual ~SkImageRef_ashmem();
     
-    // overrides
-    virtual void flatten(SkFlattenableWriteBuffer&);
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkImageRef_ashmem)
 
 protected:
+    SkImageRef_ashmem(SkFlattenableReadBuffer&);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
+
     virtual bool onDecode(SkImageDecoder* codec, SkStream* stream,
                           SkBitmap* bitmap, SkBitmap::Config config,
                           SkImageDecoder::Mode mode);
@@ -35,7 +36,6 @@
     virtual void onUnlockPixels();
     
 private:
-    SkImageRef_ashmem(SkFlattenableReadBuffer&);
     void closeFD();
 
     SkColorTable* fCT;
diff --git a/src/utils/SkUnitMappers.cpp b/src/utils/SkUnitMappers.cpp
index dd23880..df9771d 100644
--- a/src/utils/SkUnitMappers.cpp
+++ b/src/utils/SkUnitMappers.cpp
@@ -33,7 +33,7 @@
     fScale = rb.readU32();
 }
 
-void SkDiscreteMapper::flatten(SkFlattenableWriteBuffer& wb) {
+void SkDiscreteMapper::flatten(SkFlattenableWriteBuffer& wb) const {
     this->INHERITED::flatten(wb);
 
     wb.write32(fSegments);