switch xfermodes over to sk_sp

src/effects/SkLayerDrawLooper.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #include "SkCanvas.h"
 #include "SkColor.h"
 #include "SkReadBuffer.h"
 #include "SkWriteBuffer.h"
@@ skipping 86 matching lines @@
     if (bits & kMaskFilter_Bit) {
         dst->setMaskFilter(src.getMaskFilter());
     }
     if (bits & kShader_Bit) {
         dst->setShader(sk_ref_sp(src.getShader()));
     }
     if (bits & kColorFilter_Bit) {
         dst->setColorFilter(sk_ref_sp(src.getColorFilter()));
     }
     if (bits & kXfermode_Bit) {
-        dst->setXfermode(src.getXfermode());
+        dst->setXfermode(sk_ref_sp(src.getXfermode()));
     }
 
     // we don't override these
 #if 0
     dst->setTypeface(src.getTypeface());
     dst->setTextSize(src.getTextSize());
     dst->setTextScaleX(src.getTextScaleX());
     dst->setRasterizer(src.getRasterizer());
     dst->setLooper(src.getLooper());
     dst->setTextEncoding(src.getTextEncoding());
@@ skipping 229 matching lines @@
     SkLayerDrawLooper* looper = new SkLayerDrawLooper;
     looper->fCount = fCount;
     looper->fRecs = fRecs;
 
     fCount = 0;
     fRecs = nullptr;
     fTopRec = nullptr;
 
     return sk_sp<SkDrawLooper>(looper);
 }