switch xfermodes over to sk_sp

tools/debugger/SkDebugCanvas.cpp

Index: tools/debugger/SkDebugCanvas.cpp
diff --git a/tools/debugger/SkDebugCanvas.cpp b/tools/debugger/SkDebugCanvas.cpp
index 4c58b966080b56aaf047fc987da068bdb1dc9554..4fc48d849f9b3667b937bc1f953f47436a2ad383 100644
--- a/tools/debugger/SkDebugCanvas.cpp
+++ b/tools/debugger/SkDebugCanvas.cpp
@@ -33,7 +33,7 @@ public:
                            bool overrideFilterQuality,
                            SkFilterQuality quality)
         : INHERITED(width, height)
-        , fOverdrawXfermode(overdrawViz ? SkOverdrawMode::Create() : nullptr)
+        , fOverdrawXfermode(overdrawViz ? SkOverdrawMode::Make() : nullptr)
         , fOverrideFilterQuality(overrideFilterQuality)
         , fFilterQuality(quality) {}
 
@@ -42,7 +42,7 @@ protected:
         if (*paint) {
             if (nullptr != fOverdrawXfermode.get()) {
                 paint->writable()->setAntiAlias(false);
-                paint->writable()->setXfermode(fOverdrawXfermode.get());
+                paint->writable()->setXfermode(fOverdrawXfermode);
             }
 
             if (fOverrideFilterQuality) {
@@ -60,7 +60,7 @@ protected:
     }
 
 private:
-    SkAutoTUnref<SkXfermode> fOverdrawXfermode;
+    sk_sp<SkXfermode> fOverdrawXfermode;
 
     bool fOverrideFilterQuality;
     SkFilterQuality fFilterQuality;