Update nanobench so the non-MPD path doesn't permit layer hoisting

bench/nanobench.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 <ctype.h>
 
 #include "Benchmark.h"
@@ skipping 530 matching lines @@
                 }
 
                 while (fCurrentUseMPD < fUseMPDs.count()) {
                     if (FLAGS_bbh) {
                         // The SKP we read off disk doesn't have a BBH.  Re-record so it grows one.
                         SkRTreeFactory factory;
                         SkPictureRecorder recorder;
                         static const int kFlags = SkPictureRecorder::kComputeSaveLayerInfo_RecordFlag;
                         pic->playback(recorder.beginRecording(pic->cullRect().width(),
                                                               pic->cullRect().height(),
-                                                              &factory, kFlags));
+                                                              &factory, 
+                                                              fUseMPDs[fCurrentUseMPD] ? kFlags : 0));
                         pic.reset(recorder.endRecording());
                     }
                     SkString name = SkOSPath::Basename(path.c_str());
                     fSourceType = "skp";
                     fBenchType = "playback";
                     return SkNEW_ARGS(SKPBench,
                             (name.c_str(), pic.get(), fClip,
                              fScales[fCurrentScale], fUseMPDs[fCurrentUseMPD++]));
                 }
                 fCurrentUseMPD = 0;
@@ skipping 233 matching lines @@
 
     return 0;
 }
 
 #if !defined SK_BUILD_FOR_IOS
 int main(int argc, char** argv) {
     SkCommandLineFlags::Parse(argc, argv);
     return nanobench_main();
 }
 #endif