skia: Holding onto the image in the benchmark causes issues

bench/ImageBench.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 "Benchmark.h"
 #include "SkCanvas.h"
 #include "SkImage.h"
@@ skipping 21 matching lines @@
         // create an Image reflecting the canvas (gpu or cpu)
         SkImageInfo info = SkImageInfo::MakeN32Premul(100, 100);
         SkAutoTUnref<SkSurface> surface(canvas->newSurface(info));
         canvas->drawColor(SK_ColorRED);
         fImage.reset(surface->newImageSnapshot());
 
         // create a cpu-backed Surface
         fRasterSurface.reset(SkSurface::NewRaster(info));
     }
 
+    void onPerCanvasPostDraw(SkCanvas*) override {
+        // Release the image and raster surface here to prevent out of order destruction
+        // between these and the gpu interface.
+        fRasterSurface.reset(nullptr);
+        fImage.reset(nullptr);
+    }
+
     void onDraw(int loops, SkCanvas*) override {
         for (int i = 0; i < loops; i++) {
             for (int inner = 0; inner < 10; ++inner) {
                 fRasterSurface->getCanvas()->drawImage(fImage, 0, 0);
             }
         }
     }
 
 private:
     SkString                fName;
     SkAutoTUnref<SkImage>   fImage;
     SkAutoTUnref<SkSurface> fRasterSurface;
 
     typedef Benchmark INHERITED;
 };
 
 
 DEF_BENCH( return new Image2RasterBench; )