Add loopSKP flag to nanobench

bench/Benchmark.h

Index: bench/Benchmark.h
diff --git a/bench/Benchmark.h b/bench/Benchmark.h
index 22b52ab4e879d65d061320b49f611697c7e375cf..30ceb88acbb4bcaeb60fa945bc50c426a929a64c 100644
--- a/bench/Benchmark.h
+++ b/bench/Benchmark.h
@@ -65,6 +65,10 @@ public:
         return backend != kNonRendering_Backend;
     }
 
+    virtual int calculateLoops(int defaultLoops) const {
+        return defaultLoops;
+    }
+
     // Call before draw, allows the benchmark to do setup work outside of the
     // timer. When a benchmark is repeatedly drawn, this should be called once
     // before the initial draw.