Simplify flattening to just write enough to call the factory

src/effects/SkBlurImageFilter.cpp

 /*
  * Copyright 2011 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmap.h"
 #include "SkBlurImageFilter.h"
 #include "SkColorPriv.h"
 #include "SkReadBuffer.h"
 #include "SkWriteBuffer.h"
 #include "SkGpuBlurUtils.h"
 #include "SkBlurImage_opts.h"
 #if SK_SUPPORT_GPU
 #include "GrContext.h"
 #endif
 
 // This rather arbitrary-looking value results in a maximum box blur kernel size
 // of 1000 pixels on the raster path, which matches the WebKit and Firefox
 // implementations. Since the GPU path does not compute a box blur, putting
 // the limit on sigma ensures consistent behaviour between the GPU and
 // raster paths.
 #define MAX_SIGMA SkIntToScalar(532)
 
+#ifdef SK_SUPPORT_LEGACY_DEEPFLATTENING
 SkBlurImageFilter::SkBlurImageFilter(SkReadBuffer& buffer)
   : INHERITED(1, buffer) {
     fSigma.fWidth = buffer.readScalar();
     fSigma.fHeight = buffer.readScalar();
     buffer.validate(SkScalarIsFinite(fSigma.fWidth) &&
                     SkScalarIsFinite(fSigma.fHeight) &&
                     (fSigma.fWidth >= 0) &&
                     (fSigma.fHeight >= 0));
 }
+#endif
 
 SkBlurImageFilter::SkBlurImageFilter(SkScalar sigmaX,
                                      SkScalar sigmaY,
                                      SkImageFilter* input,
                                      const CropRect* cropRect)
     : INHERITED(1, &input, cropRect), fSigma(SkSize::Make(sigmaX, sigmaY)) {
     SkASSERT(sigmaX >= 0 && sigmaY >= 0);
 }
 
+SkFlattenable* SkBlurImageFilter::CreateProc(SkReadBuffer& buffer) {
+    SK_IMAGEFILTER_UNFLATTEN_COMMON(common, 1);
+    SkScalar sigmaX = buffer.readScalar();
+    SkScalar sigmaY = buffer.readScalar();
+    return Create(sigmaX, sigmaY, common.getInput(0), &common.cropRect());
+}
+
 void SkBlurImageFilter::flatten(SkWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     buffer.writeScalar(fSigma.fWidth);
     buffer.writeScalar(fSigma.fHeight);
 }
 
 enum BlurDirection {
     kX, kY
 };
 
@@ skipping 228 matching lines @@
                                                              true,
                                                              sigma.x(),
                                                              sigma.y()));
     WrapTexture(tex, rect.width(), rect.height(), result);
     return true;
 #else
     SkDEBUGFAIL("Should not call in GPU-less build");
     return false;
 #endif
 }