Simplify flattening to just write enough to call the factory

src/effects/SkMatrixConvolutionImageFilter.cpp

Index: src/effects/SkMatrixConvolutionImageFilter.cpp
diff --git a/src/effects/SkMatrixConvolutionImageFilter.cpp b/src/effects/SkMatrixConvolutionImageFilter.cpp
index 6e1d1a46521656bbfe7d196c1dad36b2572175e1..49e01b34873e7b54a26f1f3b83c83ca017b8aaa9 100644
--- a/src/effects/SkMatrixConvolutionImageFilter.cpp
+++ b/src/effects/SkMatrixConvolutionImageFilter.cpp
@@ -17,18 +17,6 @@
 #include "effects/GrMatrixConvolutionEffect.h"
 #endif
 
-static bool tile_mode_is_valid(SkMatrixConvolutionImageFilter::TileMode tileMode) {
-    switch (tileMode) {
-    case SkMatrixConvolutionImageFilter::kClamp_TileMode:
-    case SkMatrixConvolutionImageFilter::kRepeat_TileMode:
-    case SkMatrixConvolutionImageFilter::kClampToBlack_TileMode:
-        return true;
-    default:
-        break;
-    }
-    return false;
-}
-
 SkMatrixConvolutionImageFilter::SkMatrixConvolutionImageFilter(
     const SkISize& kernelSize,
     const SkScalar* kernel,
@@ -54,6 +42,19 @@ SkMatrixConvolutionImageFilter::SkMatrixConvolutionImageFilter(
     SkASSERT(kernelOffset.fY >= 0 && kernelOffset.fY < kernelSize.fHeight);
 }
 
+#ifdef SK_SUPPORT_LEGACY_DEEPFLATTENING
+static bool tile_mode_is_valid(SkMatrixConvolutionImageFilter::TileMode tileMode) {
+    switch (tileMode) {
+        case SkMatrixConvolutionImageFilter::kClamp_TileMode:
+        case SkMatrixConvolutionImageFilter::kRepeat_TileMode:
+        case SkMatrixConvolutionImageFilter::kClampToBlack_TileMode:
+            return true;
+        default:
+            break;
+    }
+    return false;
+}
+
 SkMatrixConvolutionImageFilter::SkMatrixConvolutionImageFilter(SkReadBuffer& buffer)
     : INHERITED(1, buffer) {
     // We need to be able to read at most SK_MaxS32 bytes, so divide that
@@ -86,6 +87,31 @@ SkMatrixConvolutionImageFilter::SkMatrixConvolutionImageFilter(SkReadBuffer& buf
                     (fKernelOffset.fX >= 0) && (fKernelOffset.fX < fKernelSize.fWidth) &&
                     (fKernelOffset.fY >= 0) && (fKernelOffset.fY < fKernelSize.fHeight));
 }
+#endif
+
+SkFlattenable* SkMatrixConvolutionImageFilter::CreateProc(SkReadBuffer& buffer) {
+    SK_IMAGEFILTER_UNFLATTEN_COMMON(1);
+    SkISize kernelSize;
+    kernelSize.fWidth = buffer.readInt();
+    kernelSize.fHeight = buffer.readInt();
+    const int count = buffer.getArrayCount();
+    if (!buffer.validate(kernelSize.width() * kernelSize.height() == count)) {

[Stephen White, 2014/08/18 18:17:26]

Alexis should look at this. It looks like there's a potential for int 
overflow here, from which the old code above protected us.

[reed1, 2014/08/18 22:39:16]

Done.

+        return NULL;
+    }
+    SkAutoSTArray<16, SkScalar> kernel(count);
+    if (!buffer.readScalarArray(kernel.get(), count)) {
+        return NULL;
+    }
+    SkScalar gain = buffer.readScalar();
+    SkScalar bias = buffer.readScalar();
+    SkIPoint kernelOffset;
+    kernelOffset.fX = buffer.readInt();
+    kernelOffset.fY = buffer.readInt();
+    TileMode tileMode = (TileMode)buffer.readInt();
+    bool convolveAlpha = buffer.readBool();
+    return Create(kernelSize, kernel.get(), gain, bias, kernelOffset, tileMode, convolveAlpha,
+                  common.inputAt(0), &common.cropRect());
+}
 
 void SkMatrixConvolutionImageFilter::flatten(SkWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);