Bug 1923868 - Support setting Firefox as default based on installer attribution campaign r=firefox-desktop-core-reviewers ,nalexander,omc-reviewers,pdahiya

This patch adds an startup idle task that sets the browser as default if an attribution campaign id of "set_default_browser" is present on first run. This works supports an upcoming experiment where users will have the option to "download as default" via [[ https://www.mozilla.org/en-US/firefox/new/ | the stub installer marketing page ]].

Differential Revision: https://phabricator.services.mozilla.com/D225212

browser/components/asrouter/modules/ASRouterTargeting.sys.mjs

@@ -176,6 +176,12 @@ XPCOMUtils.defineLazyPreferenceGetter(
   "toolkit.profiles.storeID",
   null
 );
+XPCOMUtils.defineLazyPreferenceGetter(
+  lazy,
+  "didHandleCampaignAction",
+  "trailhead.firstrun.didHandleCampaignAction",
+  false
+);
 
 XPCOMUtils.defineLazyServiceGetters(lazy, {
   AUS: ["@mozilla.org/updates/update-service;1", "nsIApplicationUpdateService"],
@@ -258,6 +264,39 @@ function CacheListAttachedOAuthClients() {
   };
 }
 
+function CacheUnhandledCampaignAction() {
+  return {
+    _lastUpdated: 0,
+    _value: null,
+    expire() {
+      this._lastUpdated = 0;
+      this._value = null;
+    },
+    get() {
+      const now = Date.now();
+      // Don't get cached value until the action has been handled to ensure
+      // proper screen targeting in about:welcome
+      if (
+        now - this._lastUpdated >= FRECENT_SITES_UPDATE_INTERVAL ||
+        !lazy.didHandleCampaignAction
+      ) {
+        this._value = null;
+        if (!lazy.didHandleCampaignAction) {
+          const attributionData =
+            lazy.AttributionCode.getCachedAttributionData();
+          const ALLOWED_CAMPAIGN_ACTIONS = ["SET_DEFAULT_BROWSER"];
+          const campaign = attributionData?.campaign?.toUpperCase();
+          if (campaign && ALLOWED_CAMPAIGN_ACTIONS.includes(campaign)) {
+            this._value = campaign;
+          }
+        }
+        this._lastUpdated = now;
+      }
+      return this._value;
+    },
+  };
+}
+
 function CheckBrowserNeedsUpdate(
   updateInterval = FRECENT_SITES_UPDATE_INTERVAL
 ) {
@@ -326,6 +365,7 @@ export const QueryCache = {
     RecentBookmarks: new CachedTargetingGetter("getRecentBookmarks"),
     ListAttachedOAuthClients: new CacheListAttachedOAuthClients(),
     UserMonthlyActivity: new CachedTargetingGetter("getUserMonthlyActivity"),
+    UnhandledCampaignAction: new CacheUnhandledCampaignAction(),
   },
   getters: {
     doesAppNeedPin: new CachedTargetingGetter(
@@ -1066,6 +1106,17 @@ const TargetingGetters = {
     return attributionData?.campaign === "migration";
   },
 
+  /**
+   * Whether the user opted into a special message action represented by an
+   * installer attribution campaign and this choice still needs to be honored.
+   * @return {string} A special message action to be executed on first-run. For
+   * example, `"SET_DEFAULT_BROWSER"` when the user selected to set as default
+   * via the install marketing page and set default has not yet been
+   * automatically triggered, 'null' otherwise.
+   */
+  get unhandledCampaignAction() {
+    return QueryCache.queries.UnhandledCampaignAction.get();
+  },
   /**
    * The values of the height and width available to the browser to display
    * web content. The available height and width are each calculated taking