jQuery workloads: use :nth-child() in a querySelector call in each it…

…eration (WebKit#367)

This PR fixes the issue WebKit#365: jQuery test only ever marks the first todo item as completed

The bug was caused by jQuery replacing the whole todo list whenever each todo item is toggled.

Fixed it by running querySelector with :nth-child in each iteration.

Co-authored-by: Ryosuke Niwa <rniwa@webkit.org>

resources/tests.mjs

@@ -566,9 +566,8 @@ Suites.push({
             }
         }),
         new BenchmarkTestStep("CompletingAllItems", (page) => {
-            const checkboxes = page.querySelectorAll(".toggle");
-            for (let i = 0; i < numberOfItemsToAdd; i++)
-                checkboxes[i].click();
+            for (let i = 1; i <= numberOfItemsToAdd; i++)
+                page.querySelector(`li:nth-child(${i}) .toggle`).click();
         }),
         new BenchmarkTestStep("DeletingAllItems", (page) => {
             for (let i = numberOfItemsToAdd - 1; i >= 0; i--)
@@ -596,9 +595,8 @@ Suites.push({
             }
         }),
         new BenchmarkTestStep("CompletingAllItems", (page) => {
-            const checkboxes = page.querySelectorAll(".toggle");
-            for (let i = 0; i < numberOfItemsToAdd; i++)
-                checkboxes[i].click();
+            for (let i = 1; i <= numberOfItemsToAdd; i++)
+                page.querySelector(`li:nth-child(${i}) .toggle`).click();
         }),
         new BenchmarkTestStep("DeletingAllItems", (page) => {
             for (let i = numberOfItemsToAdd - 1; i >= 0; i--)