Remove SK_SUPPORT_LEGACY_DEEPFLATTENING.

src/effects/SkTestImageFilters.cpp

Index: src/effects/SkTestImageFilters.cpp
diff --git a/src/effects/SkTestImageFilters.cpp b/src/effects/SkTestImageFilters.cpp
index a414c924f30607ebdf73e41cb794075ddfa9f9f0..be991f6f837eb8741b89ca258827b6f907e2c7e1 100755
--- a/src/effects/SkTestImageFilters.cpp
+++ b/src/effects/SkTestImageFilters.cpp
@@ -80,11 +80,3 @@ void SkDownSampleImageFilter::flatten(SkWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     buffer.writeScalar(fScale);
 }
-
-#ifdef SK_SUPPORT_LEGACY_DEEPFLATTENING
-SkDownSampleImageFilter::SkDownSampleImageFilter(SkReadBuffer& buffer)
-  : INHERITED(1, buffer) {
-    fScale = buffer.readScalar();
-    buffer.validate(SkScalarIsFinite(fScale));
-}
-#endif