Revert of Remove SK_SUPPORT_LEGACY_DEEPFLATTENING.

src/effects/SkColorMatrixFilter.cpp

Index: src/effects/SkColorMatrixFilter.cpp
diff --git a/src/effects/SkColorMatrixFilter.cpp b/src/effects/SkColorMatrixFilter.cpp
index 27231b1466312402ae4930f34db39ed7ed85a79f..20702920de202637315aa730cd16948416d047bc 100644
--- a/src/effects/SkColorMatrixFilter.cpp
+++ b/src/effects/SkColorMatrixFilter.cpp
@@ -306,6 +306,15 @@
     SkASSERT(sizeof(fMatrix.fMat)/sizeof(SkScalar) == 20);
     buffer.writeScalarArray(fMatrix.fMat, 20);
 }
+
+#ifdef SK_SUPPORT_LEGACY_DEEPFLATTENING
+SkColorMatrixFilter::SkColorMatrixFilter(SkReadBuffer& buffer) : INHERITED(buffer) {
+    SkASSERT(buffer.getArrayCount() == 20);
+    if (buffer.readScalarArray(fMatrix.fMat, 20)) {
+        this->initState(fMatrix.fMat);
+    }
+}
+#endif
 
 SkFlattenable* SkColorMatrixFilter::CreateProc(SkReadBuffer& buffer) {
     SkColorMatrix matrix;