Fix crash in bench when "--mode record" is used

bench/benchmain.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 "BenchTimer.h"
 #include "ResultsWriter.h"
 #include "SkBenchLogger.h"
@@ skipping 585 matching lines @@
                     // you've got a computer clocked at several THz or have a broken benchmark.  ;)
                     //     "1B ought to be enough for anybody."
                     logger.logError(SkStringPrintf(
                         "\nCan't get %s %s to converge in %dms (%d loops)",
                          bench->getName(), config.name, FLAGS_maxMs, loopsPerIter));
                     break;
                 }
 
                 if ((benchMode == kRecord_BenchMode || benchMode == kPictureRecord_BenchMode)) {
                     // Clear the recorded commands so that they do not accumulate.
-                    canvas.reset(recordTo.beginRecording(dim.fX, dim.fY, kRecordFlags));
+                    canvas.reset(SkRef(recordTo.beginRecording(dim.fX, dim.fY, kRecordFlags)));
                 }
 
                 timer.start();
                 // Inner loop that allows us to break the run into smaller
                 // chunks (e.g. frames). This is especially useful for the GPU
                 // as we can flush and/or swap buffers to keep the GPU from
                 // queuing up too much work.
                 for (int loopCount = loopsPerIter; loopCount > 0; ) {
                     // Save and restore around each call to draw() to guarantee a pristine canvas.
                     SkAutoCanvasRestore saveRestore(canvas, true/*also save*/);
@@ skipping 100 matching lines @@
     gContextFactory.destroyContexts();
 #endif
     return 0;
 }
 
 #if !defined(SK_BUILD_FOR_IOS) && !defined(SK_BUILD_FOR_NACL)
 int main(int argc, char * const argv[]) {
     return tool_main(argc, (char**) argv);
 }
 #endif