Bug 1564861 - WorkerList should have unique keys r=Ola

Differential Revision: https://phabricator.services.mozilla.com/D38053

--HG--
extra : moz-landing-system : lando

devtools/client/application/src/components/WorkerList.js

@@ -41,7 +41,7 @@ class WorkerList extends Component {
 
     return [
       article(
-        { className: "workers-container" },
+        { className: "workers-container", key: "workers-container" },
         Localized(
           { id: "serviceworker-list-header" },
           h1({
@@ -52,6 +52,7 @@ class WorkerList extends Component {
           {},
           workers.map(worker =>
             Worker({
+              key: worker.id,
               client,
               isDebugEnabled: canDebugWorkers,
               worker,
@@ -62,6 +63,7 @@ class WorkerList extends Component {
       Localized(
         {
           id: "serviceworker-list-aboutdebugging",
+          key: "serviceworkerlist-footer",
           a: a({
             className: "aboutdebugging-plug__link",
             onClick: () => openTrustedLink("about:debugging#workers"),

devtools/client/application/test/browser/browser_application_panel_list-single-worker.js

@@ -23,10 +23,13 @@ add_task(async function() {
   info("Wait until the service worker appears in the application panel");
   await waitUntil(() => getWorkerContainers(doc).length > 0);
 
-  const workerContainer = getWorkerContainers(doc)[0];
+  let workerContainer = getWorkerContainers(doc)[0];
 
   info("Wait until the unregister button is displayed for the service worker");
-  await waitUntil(() => workerContainer.querySelector(".js-unregister-button"));
+  await waitUntil(() => {
+    workerContainer = getWorkerContainers(doc)[0];
+    return workerContainer.querySelector(".js-unregister-button");
+  });
 
   const scopeEl = workerContainer.querySelector(".js-sw-scope");
   const expectedScope =