Cleanup code related to SkFlattenable::flatten()

The following changes were made by this CL:

1. Make flatten() a protected method as callers should use
   SkFlattenableWriteBuffer to flatten an object
2. Make flatten a const method (including subclasses)
3. Mark subclass implementation of flatten with SK_OVERRIDE
4. Ensure overridden flatten impls call their parent
5. Remove no-op implementations of flatten from subclasses

Additionally, if necessary the unflattening constructor was
also moved to the protected section of the subclasses
header if it was not already there.

git-svn-id: http://skia.googlecode.com/svn/trunk@3540 2bbb7eff-a529-9590-31e7-b0007b416f81

24 files changed, 79 insertions, 81 deletions

diff --git a/src/effects/Sk1DPathEffect.cpp b/src/effects/Sk1DPathEffect.cpp
index 11170f4a46..62ca7b39b8 100644
--- a/src/effects/Sk1DPathEffect.cpp
+++ b/src/effects/Sk1DPathEffect.cpp
@@ -156,7 +156,8 @@ SkScalar SkPath1DPathEffect::begin(SkScalar contourLength) {
     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 60ec2576d3..9a9216215a 100644
--- a/src/effects/Sk2DPathEffect.cpp
+++ b/src/effects/Sk2DPathEffect.cpp
@@ -64,7 +64,8 @@ void Sk2DPathEffect::end(SkPath* dst) {}
 
 ///////////////////////////////////////////////////////////////////////////////
 
-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 @@ SkPath2DPathEffect::SkPath2DPathEffect(SkFlattenableReadBuffer& buffer)
     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 d6682226ca..b5375e602f 100644
--- a/src/effects/SkAvoidXfermode.cpp
+++ b/src/effects/SkAvoidXfermode.cpp
@@ -29,7 +29,7 @@ SkAvoidXfermode::SkAvoidXfermode(SkFlattenableReadBuffer& buffer)
     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 656f8f7d6c..3b785731fa 100644
--- a/src/effects/SkBlurDrawLooper.cpp
+++ b/src/effects/SkBlurDrawLooper.cpp
@@ -61,7 +61,8 @@ SkBlurDrawLooper::~SkBlurDrawLooper() {
     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 1446e92117..522f4b05ea 100644
--- a/src/effects/SkBlurImageFilter.cpp
+++ b/src/effects/SkBlurImageFilter.cpp
@@ -24,7 +24,7 @@ bool SkBlurImageFilter::asABlur(SkSize* sigma) const {
     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 eb64000007..306770bb65 100644
--- a/src/effects/SkBlurMaskFilter.cpp
+++ b/src/effects/SkBlurMaskFilter.cpp
@@ -24,9 +24,6 @@ public:
     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 @@ private:
     uint32_t                    fBlurFlags;
 
     SkBlurMaskFilterImpl(SkFlattenableReadBuffer&);
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
     
     typedef SkMaskFilter INHERITED;
 };
@@ -112,7 +110,7 @@ SkBlurMaskFilterImpl::SkBlurMaskFilterImpl(SkFlattenableReadBuffer& buffer)
     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 2970c7c218..3b97250930 100644
--- a/src/effects/SkColorFilters.cpp
+++ b/src/effects/SkColorFilters.cpp
@@ -50,7 +50,7 @@ public:
     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 @@ public:
     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 @@ public:
     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 @@ protected:
         }
     }
 
-    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 47ff8ad6ac..c6886250fa 100644
--- a/src/effects/SkColorMatrixFilter.cpp
+++ b/src/effects/SkColorMatrixFilter.cpp
@@ -310,7 +310,7 @@ void SkColorMatrixFilter::filterSpan16(const uint16_t src[], int count,
 
 ///////////////////////////////////////////////////////////////////////////////
 
-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 5eb94a438f..bf59a27a1b 100644
--- a/src/effects/SkCornerPathEffect.cpp
+++ b/src/effects/SkCornerPathEffect.cpp
@@ -129,7 +129,8 @@ DONE:
     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 7950d648af..88f003b4af 100644
--- a/src/effects/SkDashPathEffect.cpp
+++ b/src/effects/SkDashPathEffect.cpp
@@ -140,9 +140,10 @@ SkFlattenable::Factory SkDashPathEffect::getFactory() {
     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 089bed6757..e8c0ec9ad2 100644
--- a/src/effects/SkDiscretePathEffect.cpp
+++ b/src/effects/SkDiscretePathEffect.cpp
@@ -67,7 +67,8 @@ bool SkDiscretePathEffect::filterPath(SkPath* dst, const SkPath& src,
     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 26a5e2ec59..245ccd69df 100644
--- a/src/effects/SkEmbossMaskFilter.cpp
+++ b/src/effects/SkEmbossMaskFilter.cpp
@@ -122,11 +122,12 @@ SkEmbossMaskFilter::SkEmbossMaskFilter(SkFlattenableReadBuffer& buffer)
     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 0fcb514585..a93bd52dbb 100644
--- a/src/effects/SkGradientShader.cpp
+++ b/src/effects/SkGradientShader.cpp
@@ -174,6 +174,8 @@ public:
 
 protected:
     Gradient_Shader(SkFlattenableReadBuffer& );
+    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
+
     SkUnitMapper* fMapper;
     SkMatrix    fPtsToUnit;     // set by subclass
     SkMatrix    fDstToIndex;
@@ -190,7 +192,6 @@ protected:
     };
     Rec*        fRecs;
 
-    virtual void flatten(SkFlattenableWriteBuffer& );
     const uint16_t*     getCache16() const;
     const SkPMColor*    getCache32() const;
 
@@ -404,7 +405,7 @@ void Gradient_Shader::initCommon() {
     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);
@@ -849,22 +850,21 @@ public:
                              SkScalar* twoPointRadialParams) const SK_OVERRIDE;
     virtual GradientType asAGradient(GradientInfo* info) const SK_OVERRIDE;
 
-    virtual void flatten(SkFlattenableWriteBuffer& buffer) SK_OVERRIDE {
-        this->INHERITED::flatten(buffer);
-        buffer.writeScalar(fStart.fX);
-        buffer.writeScalar(fStart.fY);
-        buffer.writeScalar(fEnd.fX);
-        buffer.writeScalar(fEnd.fY);
-    }
-
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(Linear_Gradient)
 
 protected:
     Linear_Gradient(SkFlattenableReadBuffer& buffer)
-        : Gradient_Shader(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);
+        buffer.writeScalar(fEnd.fX);
+        buffer.writeScalar(fEnd.fY);
+    }
 
 private:
     typedef Gradient_Shader INHERITED;
@@ -1507,21 +1507,20 @@ public:
         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;
@@ -2039,21 +2038,11 @@ public:
         return true;
     }
 
-    virtual void flatten(SkFlattenableWriteBuffer& buffer) SK_OVERRIDE {
-        this->INHERITED::flatten(buffer);
-        buffer.writeScalar(fCenter1.fX);
-        buffer.writeScalar(fCenter1.fY);
-        buffer.writeScalar(fCenter2.fX);
-        buffer.writeScalar(fCenter2.fY);
-        buffer.writeScalar(fRadius1);
-        buffer.writeScalar(fRadius2);
-    }
-
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(Two_Point_Radial_Gradient)
 
 protected:
     Two_Point_Radial_Gradient(SkFlattenableReadBuffer& buffer)
-            : Gradient_Shader(buffer),
+            : INHERITED(buffer),
               fCenter1(unflatten_point(buffer)),
               fCenter2(unflatten_point(buffer)),
               fRadius1(buffer.readScalar()),
@@ -2061,6 +2050,16 @@ protected:
         init();
     };
 
+    virtual void flatten(SkFlattenableWriteBuffer& buffer) const SK_OVERRIDE {
+        this->INHERITED::flatten(buffer);
+        buffer.writeScalar(fCenter1.fX);
+        buffer.writeScalar(fCenter1.fY);
+        buffer.writeScalar(fCenter2.fX);
+        buffer.writeScalar(fCenter2.fY);
+        buffer.writeScalar(fRadius1);
+        buffer.writeScalar(fRadius2);
+    }
+
 private:
     typedef Gradient_Shader INHERITED;
     const SkPoint fCenter1;
@@ -2125,19 +2124,18 @@ public:
         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 b27026e8b9..83a204396f 100644
--- a/src/effects/SkGroupShape.cpp
+++ b/src/effects/SkGroupShape.cpp
@@ -83,7 +83,7 @@ void SkGroupShape::onDraw(SkCanvas* canvas) {
     }
 }
 
-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 f01451c4fe..10aabc4e77 100644
--- a/src/effects/SkKernel33MaskFilter.cpp
+++ b/src/effects/SkKernel33MaskFilter.cpp
@@ -73,7 +73,7 @@ bool SkKernel33ProcMaskFilter::filterMask(SkMask* dst, const SkMask& src,
     return true;
 }
 
-void SkKernel33ProcMaskFilter::flatten(SkFlattenableWriteBuffer& wb) {
+void SkKernel33ProcMaskFilter::flatten(SkFlattenableWriteBuffer& wb) const {
     this->INHERITED::flatten(wb);
     wb.write32(fPercent256);
 }
@@ -104,7 +104,7 @@ uint8_t SkKernel33MaskFilter::computeValue(uint8_t* const* srcRows) {
     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 acb3e8891f..250306ca16 100644
--- a/src/effects/SkLayerDrawLooper.cpp
+++ b/src/effects/SkLayerDrawLooper.cpp
@@ -180,7 +180,7 @@ SkLayerDrawLooper::Rec* SkLayerDrawLooper::Rec::Reverse(Rec* head) {
 
 ///////////////////////////////////////////////////////////////////////////////
 
-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 ae4eb2eb99..81263d13d1 100644
--- a/src/effects/SkLayerRasterizer.cpp
+++ b/src/effects/SkLayerRasterizer.cpp
@@ -197,7 +197,7 @@ SkLayerRasterizer::SkLayerRasterizer(SkFlattenableReadBuffer& buffer)
     }
 }
 
-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 78fabc5616..09610cd145 100644
--- a/src/effects/SkMorphologyImageFilter.cpp
+++ b/src/effects/SkMorphologyImageFilter.cpp
@@ -19,7 +19,7 @@ SkMorphologyImageFilter::SkMorphologyImageFilter(int radiusX, int radiusY)
 }
 
 
-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 b4bbaf970c..7b58ed76a8 100644
--- a/src/effects/SkPixelXorXfermode.cpp
+++ b/src/effects/SkPixelXorXfermode.cpp
@@ -18,13 +18,13 @@ SkPMColor SkPixelXorXfermode::xferColor(SkPMColor src, SkPMColor dst) {
     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 d7e2628832..68d1e1f7ff 100644
--- a/src/effects/SkRectShape.cpp
+++ b/src/effects/SkRectShape.cpp
@@ -60,7 +60,7 @@ void SkRectShape::onDraw(SkCanvas* canvas) {
     }
 }
 
-void SkRectShape::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkRectShape::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
 
     buffer.writeRect(fBounds);
@@ -74,7 +74,7 @@ SkRectShape::SkRectShape(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {
 
 ///////////////////////////////////////////////////////////////////////////////
 
-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 8b60326b40..c709dd495a 100644
--- a/src/effects/SkTableColorFilter.cpp
+++ b/src/effects/SkTableColorFilter.cpp
@@ -35,12 +35,12 @@ public:
 
     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 @@ static const uint8_t gCountNibBits[] = {
 
 #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 3a3d0e596a..fed0c5da72 100644
--- a/src/effects/SkTableMaskFilter.cpp
+++ b/src/effects/SkTableMaskFilter.cpp
@@ -71,7 +71,7 @@ SkMask::Format SkTableMaskFilter::getFormat() {
     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 688e298cc1..0dd360b476 100755
--- a/src/effects/SkTestImageFilters.cpp
+++ b/src/effects/SkTestImageFilters.cpp
@@ -32,7 +32,7 @@ bool SkOffsetImageFilter::onFilterBounds(const SkIRect& src, const SkMatrix& ctm
     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 @@ bool SkComposeImageFilter::onFilterBounds(const SkIRect& src,
            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 @@ bool SkMergeImageFilter::onFilterImage(Proxy* proxy, const SkBitmap& src,
     return true;
 }
 
-void SkMergeImageFilter::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkMergeImageFilter::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
 
     int storedCount = fCount;
@@ -307,7 +307,7 @@ bool SkColorFilterImageFilter::onFilterImage(Proxy* proxy, const SkBitmap& src,
     return true;
 }
 
-void SkColorFilterImageFilter::flatten(SkFlattenableWriteBuffer& buffer) {
+void SkColorFilterImageFilter::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     
     buffer.writeFlattenable(fColorFilter);
@@ -369,7 +369,7 @@ bool SkDownSampleImageFilter::onFilterImage(Proxy* proxy, const SkBitmap& src,
     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 c827c111c0..28b075f4e2 100644
--- a/src/effects/SkTransparentShader.cpp
+++ b/src/effects/SkTransparentShader.cpp
@@ -125,8 +125,3 @@ void SkTransparentShader::shadeSpan16(int x, int y, uint16_t span[], int count)
         memcpy(span, src, count << 1);
     }
 }
-
-void SkTransparentShader::flatten(SkFlattenableWriteBuffer& buffer) {
-    this->INHERITED::flatten(buffer);
-}
-