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

src/gpu/SkGr.cpp

 /*
  * Copyright 2010 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "SkGr.h"
 #include "SkGrPriv.h"
 
 #include "GrCaps.h"
 #include "GrContext.h"
 #include "GrDrawContext.h"
 #include "GrGpuResourcePriv.h"
 #include "GrImageIDTextureAdjuster.h"
 #include "GrTextureParamsAdjuster.h"
 #include "GrTexturePriv.h"
 #include "GrTypes.h"
 #include "GrXferProcessor.h"
 #include "GrYUVProvider.h"
 
+#include "SkBlendModePriv.h"
 #include "SkColorFilter.h"
 #include "SkConfig8888.h"
 #include "SkCanvas.h"
 #include "SkData.h"
 #include "SkErrorInternals.h"
 #include "SkMessageBus.h"
 #include "SkMipMap.h"
 #include "SkPixelRef.h"
 #include "SkPM4fPriv.h"
 #include "SkResourceCache.h"
@@ skipping 640 matching lines @@
                 grPaint->addColorFragmentProcessor(std::move(cfFP));
             } else {
                 return false;
             }
         }
     }
 
     // When the xfermode is null on the SkPaint (meaning kSrcOver) we need the XPFactory field on
     // the GrPaint to also be null (also kSrcOver).
     SkASSERT(!grPaint->getXPFactory());
-    SkXfermode* xfermode = skPaint.getXfermode();
-    if (xfermode) {
-        grPaint->setXPFactory(xfermode->asXPFactory());
+    if (!skPaint.isSrcOver()) {
+        grPaint->setXPFactory(SkBlendMode_AsXPFactory(skPaint.getBlendMode()));
     }
 
 #ifndef SK_IGNORE_GPU_DITHER
     if (skPaint.isDither() && grPaint->numColorFragmentProcessors() > 0 && !dc->isGammaCorrect()) {
         grPaint->addColorFragmentProcessor(GrDitherEffect::Make());
     }
 #endif
     return true;
 }
 
@@ skipping 108 matching lines @@
             SkErrorInternals::SetError( kInvalidPaint_SkError,
                                         "Sorry, I don't understand the filtering "
                                         "mode you asked for.  Falling back to "
                                         "MIPMaps.");
             textureFilterMode = GrTextureParams::kMipMap_FilterMode;
             break;
 
     }
     return textureFilterMode;
 }