guard rasterizer and drawlooper setters

samplecode/SamplePathEffects.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 "SampleCode.h"
 #include "SkAnimTimer.h"
 #include "SkView.h"
@@ skipping 134 matching lines @@
 
         paint.setARGB(0xFF, 0, 0xBB, 0);
         paint.setPathEffect(make_pe(3, fPhase));
         canvas->drawPath(fPath, paint);
 
         canvas->translate(0, 50);
 
         paint.setARGB(0xFF, 0, 0, 0);
         paint.setPathEffect(make_warp_pe(fPhase));
         TestRastBuilder testRastBuilder;
-        paint.setRasterizer(testRastBuilder.detachRasterizer())->unref();
+        paint.setRasterizer(testRastBuilder.detach());
         canvas->drawPath(fPath, paint);
     }
 
     bool onAnimate(const SkAnimTimer& timer) override {
         fPhase = timer.scaled(40);
         return true;
     }
 
 private:
     typedef SampleView INHERITED;
 };
 
 //////////////////////////////////////////////////////////////////////////////
 
 static SkView* MyFactory() { return new PathEffectView; }
 static SkViewRegister reg(MyFactory);