Put Supervised User deprecation notices behind a feature flag

The feature is enabled by default.  The feature flag is:
SupervisedUserDeprecationNotice.

Bug: 899017
Change-Id: Ibe8257043fae62e6bad7f98c3ec936803f75afed
Reviewed-on: https://chromium-review.googlesource.com/c/1344871Reviewed-by: Jacob Dufault <jdufault@chromium.org>
Reviewed-by: Michael Giuffrida <michaelpg@chromium.org>
Reviewed-by: Dan Erat <derat@chromium.org>
Commit-Queue: Danan S <danan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#611366}

ash/login/ui/lock_contents_view.cc

@@ -1475,7 +1475,8 @@ void LockContentsView::OnBigUserChanged() {
   }
 
   // http://crbug/866790: After Supervised Users are deprecated, remove this.
-  if (big_user->basic_user_info->type == user_manager::USER_TYPE_SUPERVISED) {
+  if (ash::features::IsSupervisedUserDeprecationNoticeEnabled() &&
+      big_user->basic_user_info->type == user_manager::USER_TYPE_SUPERVISED) {
     base::string16 message = l10n_util::GetStringUTF16(
         IDS_ASH_LOGIN_POD_LEGACY_SUPERVISED_EXPIRATION_WARNING);
     // Shows supervised user deprecation message as a persistent error bubble.

ash/public/cpp/ash_features.cc

@@ -63,6 +63,9 @@ const base::Feature kViewsLogin{"ViewsLogin", base::FEATURE_ENABLED_BY_DEFAULT};
 const base::Feature kUseBluetoothSystemInAsh{"UseBluetoothSystemInAsh",
                                              base::FEATURE_DISABLED_BY_DEFAULT};
 
+const base::Feature kSupervisedUserDeprecationNotice{
+    "SupervisedUserDeprecationNotice", base::FEATURE_ENABLED_BY_DEFAULT};
+
 bool IsDockedMagnifierEnabled() {
   return base::FeatureList::IsEnabled(kDockedMagnifier);
 }
@@ -119,5 +122,9 @@ bool IsViewsLoginEnabled() {
          base::FeatureList::IsEnabled(kViewsLogin);
 }
 
+bool IsSupervisedUserDeprecationNoticeEnabled() {
+  return base::FeatureList::IsEnabled(kSupervisedUserDeprecationNotice);
+}
+
 }  // namespace features
 }  // namespace ash

ash/public/cpp/ash_features.h

@@ -82,6 +82,9 @@ ASH_PUBLIC_EXPORT extern const base::Feature kViewsLogin;
 // Enables using the BluetoothSystem Mojo interface for Bluetooth operations.
 ASH_PUBLIC_EXPORT extern const base::Feature kUseBluetoothSystemInAsh;
 
+// Enables the Supervised User Deprecation notices.
+ASH_PUBLIC_EXPORT extern const base::Feature kSupervisedUserDeprecationNotice;
+
 ASH_PUBLIC_EXPORT bool IsDockedMagnifierEnabled();
 
 ASH_PUBLIC_EXPORT bool IsKeyboardShortcutViewerAppEnabled();
@@ -106,6 +109,8 @@ ASH_PUBLIC_EXPORT bool IsTrilinearFilteringEnabled();
 
 ASH_PUBLIC_EXPORT bool IsViewsLoginEnabled();
 
+ASH_PUBLIC_EXPORT bool IsSupervisedUserDeprecationNoticeEnabled();
+
 }  // namespace features
 }  // namespace ash
 

chrome/browser/chromeos/login/session/user_session_manager.cc

@@ -13,6 +13,7 @@
 #include <utility>
 #include <vector>
 
+#include "ash/public/cpp/ash_features.h"
 #include "ash/public/cpp/notification_utils.h"
 #include "ash/public/cpp/vector_icons/vector_icons.h"
 #include "base/base_paths.h"
@@ -1343,7 +1344,8 @@ void UserSessionManager::UserProfileInitialized(Profile* profile,
                                                 bool is_incognito_profile,
                                                 const AccountId& account_id) {
   // http://crbug/866790: After Supervised Users are deprecated, remove this.
-  if (user_manager::UserManager::Get()->IsLoggedInAsSupervisedUser())
+  if (ash::features::IsSupervisedUserDeprecationNoticeEnabled() &&
+      user_manager::UserManager::Get()->IsLoggedInAsSupervisedUser())
     ShowSupervisedUserDeprecationNotification(profile);
 
   // Demo user signed in.