Make sure SkDrawLooper objects can only be allocated on the heap.

gm/drawlooper.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 "gm.h"
 #include "SkBlurMask.h"
 #include "SkBlurMaskFilter.h"
@@ skipping 54 matching lines @@
             SkScalar        fWidth;
             SkScalar        fOffset;
             SkScalar        fBlur;
         } gParams[] = {
             { SK_ColorWHITE, SkPaint::kStroke_Style, SkIntToScalar(1)*3/4, 0, 0 },
             { SK_ColorRED, SkPaint::kStroke_Style, SkIntToScalar(4), 0, 0 },
             { SK_ColorBLUE, SkPaint::kFill_Style, 0, 0, 0 },
             { 0x88000000, SkPaint::kFill_Style, 0, SkIntToScalar(10), SkIntToScalar(3) }
         };
 
-        fLooper = new SkLayerDrawLooper;
+        SkLayerDrawLooper::Builder looperBuilder;
 
         SkLayerDrawLooper::LayerInfo info;
         info.fPaintBits = SkLayerDrawLooper::kStyle_Bit | SkLayerDrawLooper::kMaskFilter_Bit;
         info.fColorMode = SkXfermode::kSrc_Mode;
 
         for (size_t i = 0; i < SK_ARRAY_COUNT(gParams); i++) {
             info.fOffset.set(gParams[i].fOffset, gParams[i].fOffset);
-            SkPaint* paint = fLooper->addLayer(info);
+            SkPaint* paint = looperBuilder.addLayer(info);
             paint->setColor(gParams[i].fColor);
             paint->setStyle(gParams[i].fStyle);
             paint->setStrokeWidth(gParams[i].fWidth);
             if (gParams[i].fBlur > 0) {
                 SkMaskFilter* mf = SkBlurMaskFilter::Create(SkBlurMaskFilter::kNormal_BlurStyle,
                                          SkBlurMask::ConvertRadiusToSigma(gParams[i].fBlur));
                 paint->setMaskFilter(mf)->unref();
             }
         }
+        fLooper = looperBuilder.detachLooper();
     }
 
     typedef GM INHERITED;
 };
 
 //////////////////////////////////////////////////////////////////////////////
 
 static skiagm::GM* MyFactory(void*) { return new DrawLooperGM; }
 static skiagm::GMRegistry reg(MyFactory);