Bug 1399242 - Add DAMP test to track performance of background panels. r=nchevobbe

MozReview-Commit-ID: JwZaa3AA0iN

--HG--
extra : rebase_source : 91a2fc3003bc191a4408c5671f49094a7b2ec504

testing/talos/talos/tests/devtools/addon/content/damp.html

@@ -33,6 +33,8 @@ var defaultConfig = {
     "console.objectexpand": true,
     "console.openwithcache": true,
     "inspector.mutations": true,
+
+    "panelsInBackground.reload": true,
   }
 };
 
@@ -60,6 +62,8 @@ var testsInfo = {
   "console.objectexpand": "Measure time to expand a large object and close the console",
   "console.openwithcache": "Measure time to render last logged messages in console for a page with 100 logged messages",
   "inspector.mutations": "Measure the time to perform childList mutations when inspector is enabled",
+
+  "panelsInBackground.reload": "Measure page reload time when all panels are in background",
 };
 
 function updateConfig() {

testing/talos/talos/tests/devtools/addon/content/damp.js

@@ -456,6 +456,28 @@ async _consoleOpenWithCachedMessagesTest() {
     await this.testTeardown();
   },
 
+  async _panelsInBackgroundReload() {
+    let url = "data:text/html;charset=UTF-8," + encodeURIComponent(`
+      <script>
+      // Log a significant amount of messages
+      for(let i = 0; i < 2000; i++) {
+        console.log("log in background", i);
+      }
+      </script>
+    `);
+    await this.testSetup(url);
+    let {toolbox} = await this.openToolbox("webconsole");
+
+    // Select the options panel to make the console be in background.
+    // Options panel should not do anything on page reload.
+    await toolbox.selectTool("options");
+
+    await this.reloadPageAndLog("panelsInBackground");
+
+    await this.closeToolbox();
+    await this.testTeardown();
+  },
+
   _getToolLoadingTests(url, label, { expectedMessages, expectedSources }) {
     let tests = {
       inspector: Task.async(function* () {
@@ -738,6 +760,8 @@ async _consoleOpenWithCachedMessagesTest() {
       tests["cold.inspector"] = this._coldInspectorOpen;
     }
 
+    tests["panelsInBackground.reload"] = this._panelsInBackgroundReload;
+
     Object.assign(tests, this._getToolLoadingTests(SIMPLE_URL, "simple", {
       expectedMessages: 1,
       expectedSources: 1,