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

src/core/SkRasterPipelineBlitter.cpp

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBlitter.h"
 #include "SkColor.h"
 #include "SkColorFilter.h"
@@ skipping 64 matching lines @@
                                            const SkPaint& paint,
                                            SkTBlitterAllocator* alloc) {
     if (!supported(dst.info())) {
         return nullptr;
     }
     if (paint.getShader()) {
         return nullptr;  // TODO: need to work out how shaders and their contexts work
     }
 
     SkRasterPipeline shader, colorFilter, xfermode;
-    if (!append_effect_stages(paint.getColorFilter(), &colorFilter) ||
-        !append_effect_stages(paint.getXfermode(),    &xfermode   )) {
+    if (!append_effect_stages(paint.getColorFilter(),                 &colorFilter) ||
+        !append_effect_stages(SkXfermode::Peek(paint.getBlendMode()), &xfermode   )) {
         return nullptr;
     }
 
     uint32_t paintColor = paint.getColor();
 
     SkColor4f color;
     if (SkImageInfoIsGammaCorrect(dst.info())) {
         color = SkColor4f::FromColor(paintColor);
     } else {
         swizzle_rb(SkNx_cast<float>(Sk4b::Load(&paintColor)) * (1/255.0f)).store(&color);
     }
 
     auto blitter = alloc->createT<SkRasterPipelineBlitter>(
             dst,
             shader, colorFilter, xfermode,
             color.premul());
 
     if (!paint.getShader()) {
         blitter->fShader.append(SkRasterPipeline::constant_color, &blitter->fPaintColor);
     }
-    if (!paint.getXfermode()) {
+    if (paint.isSrcOver()) {
         blitter->fXfermode.append(SkRasterPipeline::srcover);
     }
 
     return blitter;
 }
 
 void SkRasterPipelineBlitter::append_load_d(SkRasterPipeline* p, const void* dst) const {
     SkASSERT(supported(fDst.info()));
 
     switch (fDst.info().colorType()) {
@@ skipping 88 matching lines @@
             case SkMask::kLCD16_Format:
                 p.append(SkRasterPipeline::lerp_565, mask.getAddrLCD16(x,y)-x);
                 break;
             default: break;
         }
         this->append_store(&p, dst);
 
         p.run(x, clip.width());
     }
 }