Revert[8] "replace SkXfermode obj with SkBlendMode enum in paints"

samplecode/SampleLayers.cpp

Index: samplecode/SampleLayers.cpp
diff --git a/samplecode/SampleLayers.cpp b/samplecode/SampleLayers.cpp
index 52e6593a85f1e0f1975dbee6cab6affc01c343f2..71b2e8ba66c292483428adc6e22f2e88978ca447 100644
--- a/samplecode/SampleLayers.cpp
+++ b/samplecode/SampleLayers.cpp
@@ -31,7 +31,7 @@ static void make_paint(SkPaint* paint, const SkMatrix& localMatrix) {
     SkPoint pts[] = { { 0, 0 }, { 0, SK_Scalar1*20 } };
     paint->setShader(SkGradientShader::MakeLinear(pts, colors, nullptr, 2,
                                                   SkShader::kClamp_TileMode, 0, &localMatrix));
-    paint->setXfermodeMode(SkXfermode::kDstIn_Mode);
+    paint->setBlendMode(SkBlendMode::kDstIn);
 }
 
 // test drawing with strips of fading gradient above and below
@@ -141,7 +141,7 @@ protected:
             canvas->saveLayer(&r, &p);
             canvas->drawColor(0xFFFF0000);
             p.setAlpha(0);  // or 0
-            p.setXfermodeMode(SkXfermode::kSrc_Mode);
+            p.setBlendMode(SkBlendMode::kSrc);
             canvas->drawOval(r, p);
             canvas->restore();
             return;