CrOS Help: Add flag for new help app. When off, show the old help app.

Add a new flag HelpApp (--enable-features=HelpApp) for the new Chrome OS
help app, disabled by default. If this flag is turned on, the old help
app (called the Genius app) will not be shown in the launcher.

BUG=1012578

Change-Id: I093bb905b856aeb9c8a4c629cd5909d53162ac90
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1855538Reviewed-by: Trent Apted <tapted@chromium.org>
Reviewed-by: Karan Bhatia <karandeepb@chromium.org>
Auto-Submit: Patti <patricialor@chromium.org>
Commit-Queue: Karan Bhatia <karandeepb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#706151}

chrome/browser/extensions/component_loader.cc

@@ -506,14 +506,16 @@ void ComponentLoader::AddDefaultComponentExtensionsWithBackgroundPages(
   }
 
 #if defined(OS_CHROMEOS) && BUILDFLAG(GOOGLE_CHROME_BRANDING)
-  // Since this is a v2 app it has a background page.
-  AddWithNameAndDescription(
-      IDR_GENIUS_APP_MANIFEST,
-      base::FilePath(
-          FILE_PATH_LITERAL("/usr/share/chromeos-assets/genius_app")),
-      l10n_util::GetStringUTF8(IDS_GENIUS_APP_NAME),
-      l10n_util::GetStringFUTF8(IDS_GENIUS_APP_DESCRIPTION,
-                                ui::GetChromeOSDeviceName()));
+  if (!base::FeatureList::IsEnabled(chromeos::features::kHelpAppV2)) {
+    // Since this is a v2 Chrome app it has a background page.
+    AddWithNameAndDescription(
+        IDR_GENIUS_APP_MANIFEST,
+        base::FilePath(
+            FILE_PATH_LITERAL("/usr/share/chromeos-assets/genius_app")),
+        l10n_util::GetStringUTF8(IDS_GENIUS_APP_NAME),
+        l10n_util::GetStringFUTF8(IDS_GENIUS_APP_DESCRIPTION,
+                                  ui::GetChromeOSDeviceName()));
+  }
 #endif
 
   if (!skip_session_components) {

chromeos/constants/chromeos_features.cc

@@ -127,6 +127,9 @@ const base::Feature kGesturePropertiesDBusService{
 const base::Feature kGaiaActionButtons{"GaiaActionButtons",
                                        base::FEATURE_DISABLED_BY_DEFAULT};
 
+// The new ChromeOS Help App. https://crbug.com/1012578.
+const base::Feature kHelpAppV2{"HelpAppV2", base::FEATURE_DISABLED_BY_DEFAULT};
+
 // Enable or disable Unified Input Logic for HMM decoder in the IME extension
 // on Chrome OS.
 const base::Feature kImeInputLogicHmm{"ImeInputLogicHmm",

chromeos/constants/chromeos_features.h

@@ -63,6 +63,7 @@ COMPONENT_EXPORT(CHROMEOS_CONSTANTS)
 extern const base::Feature kGaiaActionButtons;
 COMPONENT_EXPORT(CHROMEOS_CONSTANTS)
 extern const base::Feature kGesturePropertiesDBusService;
+COMPONENT_EXPORT(CHROMEOS_CONSTANTS) extern const base::Feature kHelpAppV2;
 COMPONENT_EXPORT(CHROMEOS_CONSTANTS)
 extern const base::Feature kImeInputLogicHmm;
 COMPONENT_EXPORT(CHROMEOS_CONSTANTS)