remove xfermode from public api

BUG=skia:

GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=4020

CQ_INCLUDE_TRYBOTS=master.client.skia:Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-SKNX_NO_SIMD-Trybot

Change-Id: I19cd056f2af778f10e8c6c2b7b2735593b43dbac
Reviewed-on: https://skia-review.googlesource.com/4020
Reviewed-by: Florin Malita <fmalita@chromium.org>
Reviewed-by: Mike Klein <mtklein@chromium.org>
Commit-Queue: Mike Reed <reed@google.com>
diff --git a/bench/BlurRoundRectBench.cpp b/bench/BlurRoundRectBench.cpp
index 713996c..123e889 100644
--- a/bench/BlurRoundRectBench.cpp
+++ b/bench/BlurRoundRectBench.cpp
@@ -45,7 +45,7 @@
             SkLayerDrawLooper::LayerInfo info;
             info.fPaintBits = SkLayerDrawLooper::kMaskFilter_Bit
                               | SkLayerDrawLooper::kColorFilter_Bit;
-            info.fColorMode = SkXfermode::kSrc_Mode;
+            info.fColorMode = (SK_XFERMODE_MODE_PARAM)SkBlendMode::kSrc;
             info.fOffset = SkPoint::Make(SkIntToScalar(-1), SkIntToScalar(0));
             info.fPostTranslate = false;
             SkPaint* paint = looperBuilder.addLayerOnTop(info);
@@ -53,7 +53,7 @@
                                                         SkBlurMask::ConvertRadiusToSigma(0.5),
                                                         SkBlurMaskFilter::kHighQuality_BlurFlag));
             paint->setColorFilter(SkColorFilter::MakeModeFilter(SK_ColorLTGRAY,
-                                                                SkXfermode::kSrcIn_Mode));
+                                                                SkBlendMode::kSrcIn));
             paint->setColor(SK_ColorGRAY);
         }
         {