Add loopSKP flag to nanobench

bench/SKPBench.h

Index: bench/SKPBench.h
diff --git a/bench/SKPBench.h b/bench/SKPBench.h
index 3b645e97346df2d13bd428794caa82324ed56069..e1c66bf2ecfe5029ef0c4736872f5d9ddd3b70e7 100644
--- a/bench/SKPBench.h
+++ b/bench/SKPBench.h
@@ -18,9 +18,13 @@
 class SKPBench : public Benchmark {
 public:
     SKPBench(const char* name, const SkPicture*, const SkIRect& devClip, SkScalar scale,
-             bool useMultiPictureDraw);
+             bool useMultiPictureDraw, bool doLooping);
     ~SKPBench() override;
 
+    int calculateLoops(int defaultLoops) const override {
+        return fDoLooping ? defaultLoops : 1;
+    }
+
 protected:
     const char* onGetName() override;
     const char* onGetUniqueName() override;
@@ -48,6 +52,8 @@ private:
     SkTDArray<SkSurface*> fSurfaces;   // for MultiPictureDraw
     SkTDArray<SkIRect> fTileRects;     // for MultiPictureDraw
 
+    const bool fDoLooping;
+
     typedef Benchmark INHERITED;
 };