Add samplingTime mode to nanobench

tools/Stats.h

Index: tools/Stats.h
diff --git a/tools/Stats.h b/tools/Stats.h
index 8487a9497da6dff23cf2508dad5831065deeaa29..2a75f07f06e7200e2192933849ce87290306f3e7 100644
--- a/tools/Stats.h
+++ b/tools/Stats.h
@@ -11,7 +11,13 @@
 #endif
 
 struct Stats {
-    Stats(const double samples[], int n) {
+    Stats(const SkTArray<double>& samples) {
+        int n = samples.count();
+        if (!n) {
+            min = max = mean = var = median = 0;
+            return;
+        }
+
         min = samples[0];
         max = samples[0];
         for (int i = 0; i < n; i++) {
@@ -32,7 +38,7 @@ struct Stats {
         var = err / (n-1);
 
         SkAutoTMalloc<double> sorted(n);
-        memcpy(sorted.get(), samples, n * sizeof(double));
+        memcpy(sorted.get(), samples.begin(), n * sizeof(double));
         SkTQSort(sorted.get(), sorted.get() + n - 1);
         median = sorted[n/2];