Add map iterator to misc benchmark.

benchmarks/misc/tests/assorted/LIST

@@ -39,3 +39,4 @@ misc-bugs-1090583-dart2js-tracer
 misc-basic-hoist-bounds-check
 misc-apply-array
 misc-apply-array-headroom
+misc-map-iterator

benchmarks/misc/tests/assorted/misc-map-iterator.js

@@ -0,0 +1,57 @@
+function assertEq(result, expected) {
+  if (result !== expected)
+    throw "Assertion: Expected " + expected + ", got " + result;
+}
+
+var loops = 10000;
+var entries = 100;
+
+var map = new Map();
+for (var i = 0; i < entries; i++)
+    map.set(i * 2, i * 3);
+
+function test_keys(m) {
+  for (var i = loops; i--;) {
+    var j = 0;
+    for (var k of m.keys()) {
+      assertEq(k, j * 2);
+      j++;
+    }
+  }
+}
+test_keys(map);
+
+function test_values(m) {
+  for (var i = loops; i--;) {
+    var j = 0;
+    for (var v of m.values()) {
+      assertEq(v, j * 3);
+      j++;
+    }
+  }
+}
+test_values(map);
+
+function test_entries(m) {
+  for (var i = loops; i--;) {
+    var j = 0;
+    for (var e of m.entries()) {
+      assertEq(e[0], j * 2);
+      assertEq(e[1], j * 3);
+      j++;
+    }
+  }
+}
+test_entries(map);
+
+function test_iterator(m) {
+  for (var i = loops; i--;) {
+    var j = 0;
+    for (var e of m) {
+      assertEq(e[0], j * 2);
+      assertEq(e[1], j * 3);
+      j++;
+    }
+  }
+}
+test_iterator(map);