use Make instead of Create to return a shared shader

samplecode/SampleXfer.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SampleCode.h"
 #include "SkAnimTimer.h"
 #include "SkDrawable.h"
@@ skipping 109 matching lines @@
     }
 };
 
 class CircDrawable : public ModeDrawable {
     SkPaint fPaint;
     SkRect  fBounds;
 
 public:
     CircDrawable(SkScalar size, SkColor c) {
         const SkColor colors[] = { 0, c };
-        SkAutoTUnref<SkShader> shader(SkGradientShader::CreateRadial(SkPoint::Make(size/2, size/2), size/2,
+        fPaint.setShader(SkGradientShader::MakeRadial(SkPoint::Make(size/2, size/2), size/2,
                                                                      colors, nullptr, 2,
                                                                      SkShader::kClamp_TileMode));
-        fPaint.setShader(shader);
         fBounds = SkRect::MakeWH(size, size);
     }
 
 protected:
     SkRect onGetBounds() override {
         return fBounds;
     }
 
     void onDraw(SkCanvas* canvas) override {
         fPaint.setXfermodeMode(fMode);
@@ skipping 99 matching lines @@
         return true;
     }
 
 private:
     typedef SampleView INHERITED;
 };
 
 //////////////////////////////////////////////////////////////////////////////
 
 DEF_SAMPLE( return new XferDemo; )