Bug 1674827 - Make sure getInfo.html waits for about:newtab's TopSitesFeed to finish initting when setting up a Talos test. r=perftest-reviewers,sparky

There was also a bug where the TalosPowersGoQuitApplication event detail was
being treated as an object even though it was actually a boolean.

This also re-enables the startup_about_home_paint_cached which was failing
intermittently because of these bugs.

Differential Revision: https://phabricator.services.mozilla.com/D137057

testing/talos/talos.json

@@ -13,8 +13,7 @@
             "tests": ["tart_flex", "ts_paint_flex"]
         },
         "other": {
-            "_comment": "Bug 1220362 - Disabled startup_about_home_paint_cached for high frequency intermittents",
-            "tests": ["a11yr", "ts_paint", "twinopen", "sessionrestore", "sessionrestore_no_auto_restore", "tabpaint", "cpstartup", "startup_about_home_paint", "pdfpaint", "cross_origin_pageload"]
+            "tests": ["a11yr", "ts_paint", "twinopen", "sessionrestore", "sessionrestore_no_auto_restore", "tabpaint", "cpstartup", "startup_about_home_paint", "pdfpaint", "cross_origin_pageload", "startup_about_home_paint_cached"]
         },
         "sessionrestore-many-windows": {
             "tests": ["sessionrestore_many_windows"]

testing/talos/talos/getInfo.html

@@ -29,7 +29,7 @@
     //  dump(`\tBrowser outer width/height: ${window.outerWidth}/${window.outerHeight}`);
     dump("\n__metrics\n");
     TalosPowersParent.exec("dumpAboutSupport");
-    TalosPowersContent.goQuitApplication(true);
+    TalosPowersContent.goQuitApplication(true /* waitForStartupFinished */);
   });
   </script>
 

testing/talos/talos/talos-powers/api.js

@@ -8,6 +8,8 @@ const { ComponentUtils } = ChromeUtils.import(
   "resource://gre/modules/ComponentUtils.jsm"
 );
 XPCOMUtils.defineLazyModuleGetters(this, {
+  AboutHomeStartupCache: "resource:///modules/BrowserGlue.jsm",
+  AboutNewTab: "resource:///modules/AboutNewTab.jsm",
   BrowserWindowTracker: "resource:///modules/BrowserWindowTracker.jsm",
   OS: "resource://gre/modules/osfile.jsm",
   PerTestCoverageUtils: "resource://testing-common/PerTestCoverageUtils.jsm",
@@ -264,7 +266,10 @@ TalosPowersService.prototype = {
   },
 
   async forceQuit(messageData) {
-    if (messageData && messageData.waitForSafeBrowsing) {
+    if (messageData && messageData.waitForStartupFinished) {
+      // We can wait for various startup items here to complete during
+      // the getInfo.html step for Talos so that subsequent runs don't
+      // have to do things like re-request the SafeBrowsing list.
       let SafeBrowsing = ChromeUtils.import(
         "resource://gre/modules/SafeBrowsing.jsm",
         {}
@@ -278,6 +283,21 @@ TalosPowersService.prototype = {
       } catch (e) {
         // We don't care if things go wrong here - let's just shut down.
       }
+
+      // We wait for the AboutNewTab's TopSitesFeed (and its "Contile"
+      // integration, which shows the sponsored Top Sites) to finish
+      // being enabled here. This is because it's possible for getInfo.html
+      // to run so quickly that the feed will still be initializing, and
+      // that would cause us to write a mostly empty cache to the
+      // about:home startup cache on shutdown, which causes that test
+      // to break periodically.
+      AboutNewTab.onBrowserReady();
+      let feed = AboutNewTab.activityStream.store.feeds.get(
+        "feeds.system.topsites"
+      );
+      await feed._contile.refresh();
+      await feed.refresh({ broadcast: true });
+      await AboutHomeStartupCache.cacheNow();
     }
 
     // Check to see if the top-most browser window still needs to fire its

testing/talos/talos/talos-powers/content/TalosPowersContent.js

@@ -96,10 +96,10 @@ var TalosPowersParent;
       document.dispatchEvent(event);
     },
 
-    goQuitApplication(waitForSafeBrowsing) {
+    goQuitApplication(waitForStartupFinished) {
       var event = new CustomEvent("TalosPowersGoQuitApplication", {
         bubbles: true,
-        detail: waitForSafeBrowsing,
+        detail: { waitForStartupFinished },
       });
       document.dispatchEvent(event);
     },