Prevent transient failures caused by slow test execution.

Testling would occasionally fail the `Promise.race` test because test
execution on the browser under test was so slow that all the delayed
promises would complete "at once".  Ensure that even if this happens
the test gives the correct answer.

test/promise/race.js

@@ -35,7 +35,12 @@ describe("Promise.race", function () {
   });
 
   it("should settle in the same way as the first promise to settle", function (done) {
-    var iterable = [delayPromise(1, 1000), delayPromise(2, 200), delayPromise(3, 500)];
+    // ensure that even if timeouts are delayed an all execute together,
+    // p2 will settle first.
+    var p2 = delayPromise(2, 200);
+    var p1 = delayPromise(1, 1000);
+    var p3 = delayPromise(3, 500);
+    var iterable = [p1, p2, p3];
 
     Promise.race(iterable).then(function (value) {
       assert.strictEqual(value, 2);