Revert of small tidy of benchmarkstream (patchset #2 id:20001 of https://codereview.chromium.org/1395703002/ )

Reason for revert:
Breaks visualbench

Original issue's description:
> small tidy of benchmarkstream
>
> BUG=skia:
>
> Committed: https://skia.googlesource.com/skia/+/691b6af907e55250a29a7a2a346b63c2026011c3

TBR=robertphillips@google.com,joshualitt@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Review URL: https://codereview.chromium.org/1392833006
diff --git a/tools/VisualBench/VisualStreamTimingModule.h b/tools/VisualBench/VisualStreamTimingModule.h
index b84f04f..ac06ed4 100644
--- a/tools/VisualBench/VisualStreamTimingModule.h
+++ b/tools/VisualBench/VisualStreamTimingModule.h
@@ -31,8 +31,11 @@
     // subclasses should return true to advance the stream
     virtual bool timingFinished(Benchmark*, int loops, double measurement)=0;
 
+    bool nextBenchmarkIfNecessary(SkCanvas*);
+
     TimingStateMachine fTSM;
     SkAutoTDelete<VisualBenchmarkStream> fBenchmarkStream;
+    SkAutoTUnref<Benchmark> fBenchmark;
     bool fReinitializeBenchmark;
     bool fPreWarmBeforeSample;