Fix the browser test HelpAppV2DiscoverTabNotification.

The browser test HelpAppV2DiscoverTabNotification is broken when the
flag kAppServiceLaunchWithoutMojom is enabled:
https://ci.chromium.org/p/chromium/builders/try/linux-chromeos-rel/1262612?

Because the non mojom launch interface runs synchronously. Replace the
asynchronously WaitForAppToOpen, with the synchronously checking after
running SimulateClick to launch the help app.

The checking ENABLE_CROS_HELP_APP can be removed, because the help app
is always launched.

BUG=1253250

Change-Id: I52f751ac52ca8bbdc1a4578ed6ca64d8c0bb1d95
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3790425
Commit-Queue: Nancy Wang <nancylingwang@chromium.org>
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Reviewed-by: Dominick Ng <dominickn@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1030082}

chrome/browser/ash/web_applications/help_app/help_app_integration_browsertest.cc

@@ -48,6 +48,7 @@
 #include "chromeos/constants/chromeos_features.h"
 #include "components/language/core/browser/pref_names.h"
 #include "components/services/app_service/public/cpp/app_launch_util.h"
+#include "components/services/app_service/public/cpp/features.h"
 #include "components/user_manager/user_names.h"
 #include "content/public/browser/browser_task_traits.h"
 #include "content/public/browser/browser_thread.h"
@@ -407,12 +408,14 @@ IN_PROC_BROWSER_TEST_P(HelpAppIntegrationTest,
                                  kShowHelpAppDiscoverTabNotificationId,
                                  absl::nullopt, absl::nullopt);
 
-#if BUILDFLAG(ENABLE_CROS_HELP_APP)
-  EXPECT_NO_FATAL_FAILURE(WaitForAppToOpen(GURL("chrome://help-app/discover")));
-#else
-  // We just have the original browser. No new app opens.
-  EXPECT_EQ(1u, chrome::GetTotalBrowserCount());
-#endif
+  if (base::FeatureList::IsEnabled(apps::kAppServiceLaunchWithoutMojom)) {
+    EXPECT_EQ(2u, chrome::GetTotalBrowserCount());
+    EXPECT_EQ(GURL("chrome://help-app/discover"),
+              GetActiveWebContents()->GetVisibleURL());
+  } else {
+    EXPECT_NO_FATAL_FAILURE(
+        WaitForAppToOpen(GURL("chrome://help-app/discover")));
+  }
 }
 
 // Test that the background page can trigger the release notes notification.