feat: 拆分 stress benchmark 到细粒度单热点测试并修复 bench 采样逻辑

tests/stress/array_sort.js

@@ -0,0 +1,13 @@
+var ITERATIONS = 500;
+
+var base = [];
+for (var i = 0; i < 100; i++) {
+  base.push(100 - i);
+}
+var sum = 0;
+for (var j = 0; j < ITERATIONS; j++) {
+  var out = base.slice();
+  out.sort(function (a, b) { return a - b; });
+  sum += out[0];
+}
+sum