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

This reverts commit c245574ba3d0e2ade6c94b2812de3baa383bf4c4.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2396953002

TBR=

Review-Url: https://codereview.chromium.org/2396953002
diff --git a/src/gpu/GrTextureToYUVPlanes.cpp b/src/gpu/GrTextureToYUVPlanes.cpp
index 5e7dafe..93a62d2 100644
--- a/src/gpu/GrTextureToYUVPlanes.cpp
+++ b/src/gpu/GrTextureToYUVPlanes.cpp
@@ -41,7 +41,7 @@
         return false;
     }
     GrPaint paint;
-    paint.setPorterDuffXPFactory(SkXfermode::kSrc_Mode);
+    paint.setPorterDuffXPFactory(SkBlendMode::kSrc);
     paint.addColorFragmentProcessor(std::move(fp));
     dst->drawRect(GrNoClip(), paint, SkMatrix::I(), SkRect::MakeIWH(dstW, dstH));
     return true;