Add test cases for notification metrics.

BUG=1068884

Change-Id: Ide76bd5cfc0f1a4ba497f0420a52fcc020f293a5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2223835Reviewed-by: Dominick Ng <dominickn@chromium.org>
Commit-Queue: Nancy Wang <nancylingwang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#773932}

chrome/browser/apps/app_service/notifications_browsertest.cc

@@ -8,6 +8,7 @@
 #include "ash/system/message_center/arc/arc_notification_manager.h"
 #include "ash/system/message_center/arc/arc_notification_manager_delegate.h"
 #include "base/run_loop.h"
+#include "base/test/metrics/histogram_tester.h"
 #include "base/test/scoped_feature_list.h"
 #include "chrome/browser/apps/app_service/app_service_proxy.h"
 #include "chrome/browser/apps/app_service/app_service_proxy_factory.h"
@@ -470,8 +471,38 @@ IN_PROC_BROWSER_TEST_P(AppNotificationsWebNotificationTest,
   ASSERT_EQ(apps::mojom::OptionalBool::kFalse, HasBadge(profile(), app_id2));
 }
 
+IN_PROC_BROWSER_TEST_P(AppNotificationsWebNotificationTest,
+                       AddAndRemoveNonPersistentNotificationForOneApp) {
+  base::HistogramTester histogram_tester;
+
+  const GURL origin = GetOrigin();
+  std::string app_id1 = CreateWebApp(GetUrl1(), GetScope1());
+  std::string app_id3 = CreateWebApp(GetUrl3(), GetScope3());
+
+  ASSERT_EQ(apps::mojom::OptionalBool::kFalse, HasBadge(profile(), app_id1));
+  ASSERT_EQ(apps::mojom::OptionalBool::kFalse, HasBadge(profile(), app_id3));
+
+  const std::string notification_id = "notification-id";
+  auto notification = CreateNotification(notification_id, origin);
+
+  NotificationDisplayService::GetForProfile(profile())->Display(
+      NotificationHandler::Type::WEB_NON_PERSISTENT, *notification,
+      /*metadata=*/nullptr);
+  ASSERT_EQ(apps::mojom::OptionalBool::kTrue, HasBadge(profile(), app_id1));
+  ASSERT_EQ(apps::mojom::OptionalBool::kFalse, HasBadge(profile(), app_id3));
+
+  histogram_tester.ExpectUniqueSample(
+      "ChromeOS.Apps.NumberOfAppsForNotification", false, 1);
+
+  RemoveNotification(profile(), notification_id);
+  ASSERT_EQ(apps::mojom::OptionalBool::kFalse, HasBadge(profile(), app_id1));
+  ASSERT_EQ(apps::mojom::OptionalBool::kFalse, HasBadge(profile(), app_id3));
+}
+
 IN_PROC_BROWSER_TEST_P(AppNotificationsWebNotificationTest,
                        AddAndRemoveNonPersistentNotification) {
+  base::HistogramTester histogram_tester;
+
   const GURL origin = GetOrigin();
   std::string app_id1 = CreateWebApp(GetUrl1(), GetScope1());
   std::string app_id2 = CreateWebApp(GetUrl2(), GetScope2());
@@ -491,6 +522,9 @@ IN_PROC_BROWSER_TEST_P(AppNotificationsWebNotificationTest,
   ASSERT_EQ(apps::mojom::OptionalBool::kTrue, HasBadge(profile(), app_id2));
   ASSERT_EQ(apps::mojom::OptionalBool::kFalse, HasBadge(profile(), app_id3));
 
+  histogram_tester.ExpectUniqueSample(
+      "ChromeOS.Apps.NumberOfAppsForNotification", true, 1);
+
   RemoveNotification(profile(), notification_id);
   ASSERT_EQ(apps::mojom::OptionalBool::kFalse, HasBadge(profile(), app_id1));
   ASSERT_EQ(apps::mojom::OptionalBool::kFalse, HasBadge(profile(), app_id2));
@@ -499,6 +533,8 @@ IN_PROC_BROWSER_TEST_P(AppNotificationsWebNotificationTest,
 
 IN_PROC_BROWSER_TEST_P(AppNotificationsWebNotificationTest,
                        NonPersistentNotificationWhenInstallAndUninstallApp) {
+  base::HistogramTester histogram_tester;
+
   // Send the notification 1 before installing apps.
   const GURL origin = GetOrigin();
   const std::string notification_id1 = "notification-id1";
@@ -517,6 +553,9 @@ IN_PROC_BROWSER_TEST_P(AppNotificationsWebNotificationTest,
   ASSERT_EQ(apps::mojom::OptionalBool::kFalse, HasBadge(profile(), app_id2));
   ASSERT_EQ(apps::mojom::OptionalBool::kFalse, HasBadge(profile(), app_id3));
 
+  histogram_tester.ExpectTotalCount("ChromeOS.Apps.NumberOfAppsForNotification",
+                                    0);
+
   // Send the notification 2.
   const std::string notification_id2 = "notification-id2";
   notification = CreateNotification(notification_id2, origin);
@@ -529,6 +568,9 @@ IN_PROC_BROWSER_TEST_P(AppNotificationsWebNotificationTest,
   ASSERT_EQ(apps::mojom::OptionalBool::kTrue, HasBadge(profile(), app_id2));
   ASSERT_EQ(apps::mojom::OptionalBool::kFalse, HasBadge(profile(), app_id3));
 
+  histogram_tester.ExpectUniqueSample(
+      "ChromeOS.Apps.NumberOfAppsForNotification", true, 1);
+
   // Uninstall the app 1. The notification badge for app 2 and app 3 should not
   // be affected.
   UninstallWebApp(app_id1);
@@ -552,6 +594,9 @@ IN_PROC_BROWSER_TEST_P(AppNotificationsWebNotificationTest,
   ASSERT_EQ(apps::mojom::OptionalBool::kTrue, HasBadge(profile(), app_id2));
   ASSERT_EQ(apps::mojom::OptionalBool::kFalse, HasBadge(profile(), app_id3));
 
+  histogram_tester.ExpectUniqueSample(
+      "ChromeOS.Apps.NumberOfAppsForNotification", true, 2);
+
   // Remove the notification 3
   RemoveNotification(profile(), notification_id3);
   ASSERT_EQ(apps::mojom::OptionalBool::kFalse, HasBadge(profile(), app_id1));