add some debugging to SkNVRefCnt

bench/RecordingBench.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "RecordingBench.h"
 
 #include "SkBBHFactory.h"
@@ skipping 19 matching lines @@
 
 void RecordingBench::onDraw(const int loops, SkCanvas*) {
     SkRTreeFactory factory;
     const SkScalar w = fSrc->cullRect().width(),
                    h = fSrc->cullRect().height();
 
     for (int i = 0; i < loops; i++) {
         SkPictureRecorder recorder;
         fSrc->playback(recorder.beginRecording(w, h, fUseBBH ? &factory : NULL,
                                                SkPictureRecorder::kComputeSaveLayerInfo_RecordFlag));
-        SkDELETE(recorder.endRecording());
+        SkSafeUnref(recorder.endRecording());
     }
 }