Disabled settings icon via SystemFeaturesDisableList

Disabled the settings icon in the system tray when os settings is added
in SystemFeaturesDisableList policy

Bug: 1066795
Change-Id: I6131e5cb05b0e305f0d9007391d7cd5c1231adf8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2130855Reviewed-by: Tim Song <tengs@chromium.org>
Reviewed-by: Ahmed Fakhry <afakhry@chromium.org>
Reviewed-by: Sergey Poromov <poromov@chromium.org>
Commit-Queue: Aya Elsayed <ayaelattar@google.com>
Cr-Commit-Position: refs/heads/master@{#758769}

ash/ash_prefs.cc

@@ -27,6 +27,7 @@
 #include "ash/system/palette/palette_welcome_bubble.h"
 #include "ash/system/power/power_prefs.h"
 #include "ash/system/session/logout_button_tray.h"
+#include "ash/system/unified/top_shortcuts_view.h"
 #include "ash/touch/touch_devices_controller.h"
 #include "ash/wallpaper/wallpaper_controller_impl.h"
 #include "ash/wm/desks/desks_restore_util.h"
@@ -79,6 +80,7 @@ void RegisterLocalStatePrefs(PrefRegistrySimple* registry, bool for_test) {
   DetachableBaseHandler::RegisterPrefs(registry);
   PowerPrefs::RegisterLocalStatePrefs(registry);
   DisplayPrefs::RegisterLocalStatePrefs(registry);
+  TopShortcutsView::RegisterLocalStatePrefs(registry);
 }
 
 void RegisterSigninProfilePrefs(PrefRegistrySimple* registry, bool for_test) {

ash/public/cpp/ash_pref_names.cc

@@ -370,6 +370,10 @@ const char kPowerSmartDimEnabled[] = "power.smart_dim_enabled";
 // Boolean controlling whether ALS logging is enabled.
 const char kPowerAlsLoggingEnabled[] = "power.als_logging_enabled";
 
+// Boolean controlling whether the settings is enabled. This pref is intended to
+// be set only by policy not by user.
+const char kOsSettingsEnabled[] = "os_settings_enabled";
+
 // |kShelfAlignment| and |kShelfAutoHideBehavior| have a local variant. The
 // local variant is not synced and is used if set. If the local variant is not
 // set its value is set from the synced value (once prefs have been

ash/public/cpp/ash_pref_names.h

@@ -103,6 +103,8 @@ ASH_PUBLIC_EXPORT extern const char kNightLightCachedLatitude[];
 ASH_PUBLIC_EXPORT extern const char kNightLightCachedLongitude[];
 ASH_PUBLIC_EXPORT extern const char kAutoNightLightNotificationDismissed[];
 
+ASH_PUBLIC_EXPORT extern const char kOsSettingsEnabled[];
+
 ASH_PUBLIC_EXPORT extern const char kAllowScreenLock[];
 ASH_PUBLIC_EXPORT extern const char kEnableAutoScreenLock[];
 ASH_PUBLIC_EXPORT extern const char kPowerAcScreenBrightnessPercent[];

ash/system/unified/top_shortcuts_view.cc

@@ -7,6 +7,7 @@
 #include <numeric>
 
 #include "ash/accessibility/accessibility_controller_impl.h"
+#include "ash/public/cpp/ash_pref_names.h"
 #include "ash/public/cpp/ash_view_ids.h"
 #include "ash/resources/vector_icons/vector_icons.h"
 #include "ash/session/session_controller_impl.h"
@@ -23,7 +24,10 @@
 #include "ash/system/unified/user_chooser_detailed_view_controller.h"
 #include "ash/system/unified/user_chooser_view.h"
 #include "base/numerics/ranges.h"
+#include "components/prefs/pref_registry_simple.h"
+#include "components/prefs/pref_service.h"
 #include "ui/gfx/paint_vector_icon.h"
+#include "ui/views/controls/button/button.h"
 #include "ui/views/controls/highlight_path_generator.h"
 #include "ui/views/layout/box_layout.h"
 #include "ui/views/layout/fill_layout.h"
@@ -198,6 +202,12 @@ TopShortcutsView::TopShortcutsView(UnifiedSystemTrayController* controller)
     settings_button_ = new TopShortcutButton(this, kUnifiedMenuSettingsIcon,
                                              IDS_ASH_STATUS_TRAY_SETTINGS);
     container_->AddChildView(settings_button_);
+    local_state_pref_change_registrar_.Init(Shell::Get()->local_state());
+    local_state_pref_change_registrar_.Add(
+        prefs::kOsSettingsEnabled,
+        base::BindRepeating(&TopShortcutsView::UpdateSettingsButtonState,
+                            base::Unretained(this)));
+    UpdateSettingsButtonState();
   }
 
   // |collapse_button_| should be right-aligned, so we make the buttons
@@ -208,6 +218,11 @@ TopShortcutsView::TopShortcutsView(UnifiedSystemTrayController* controller)
   AddChildView(collapse_button_);
 }
 
+// static
+void TopShortcutsView::RegisterLocalStatePrefs(PrefRegistrySimple* registry) {
+  registry->RegisterBooleanPref(prefs::kOsSettingsEnabled, true);
+}
+
 void TopShortcutsView::SetExpandedAmount(double expanded_amount) {
   collapse_button_->SetExpandedAmount(expanded_amount);
 }
@@ -232,4 +247,14 @@ const char* TopShortcutsView::GetClassName() const {
   return "TopShortcutsView";
 }
 
+void TopShortcutsView::UpdateSettingsButtonState() {
+  PrefService* const local_state = Shell::Get()->local_state();
+  const bool settings_icon_enabled =
+      local_state->GetBoolean(prefs::kOsSettingsEnabled);
+
+  settings_button_->SetState(settings_icon_enabled
+                                 ? views::Button::STATE_NORMAL
+                                 : views::Button::STATE_DISABLED);
+}
+
 }  // namespace ash

ash/system/unified/top_shortcuts_view.h

@@ -7,9 +7,12 @@
 
 #include "ash/accessibility/accessibility_observer.h"
 #include "ash/ash_export.h"
+#include "components/prefs/pref_change_registrar.h"
 #include "ui/views/controls/button/button.h"
 #include "ui/views/view.h"
 
+class PrefRegistrySimple;
+
 namespace ash {
 
 class CollapseButton;
@@ -48,6 +51,8 @@ class ASH_EXPORT TopShortcutsView : public views::View,
  public:
   explicit TopShortcutsView(UnifiedSystemTrayController* controller);
 
+  static void RegisterLocalStatePrefs(PrefRegistrySimple* registry);
+
   // Change the expanded state. CollapseButton icon will rotate.
   void SetExpandedAmount(double expanded_amount);
 
@@ -60,6 +65,9 @@ class ASH_EXPORT TopShortcutsView : public views::View,
  private:
   friend class TopShortcutsViewTest;
 
+  // Disables/Enables the |settings_button_| based on kSettingsIconEnabled pref.
+  void UpdateSettingsButtonState();
+
   UnifiedSystemTrayController* controller_;
 
   // Owned by views hierarchy.
@@ -71,6 +79,8 @@ class ASH_EXPORT TopShortcutsView : public views::View,
   TopShortcutButton* power_button_ = nullptr;
   CollapseButton* collapse_button_ = nullptr;
 
+  PrefChangeRegistrar local_state_pref_change_registrar_;
+
   DISALLOW_COPY_AND_ASSIGN(TopShortcutsView);
 };
 

ash/system/unified/top_shortcuts_view_unittest.cc

@@ -4,6 +4,7 @@
 
 #include "ash/system/unified/top_shortcuts_view.h"
 
+#include "ash/public/cpp/ash_pref_names.h"
 #include "ash/session/test_session_controller_client.h"
 #include "ash/system/unified/collapse_button.h"
 #include "ash/system/unified/sign_out_button.h"
@@ -12,6 +13,7 @@
 #include "ash/system/unified/unified_system_tray_model.h"
 #include "ash/test/ash_test_base.h"
 #include "base/macros.h"
+#include "components/prefs/pref_registry_simple.h"
 
 namespace ash {
 
@@ -172,4 +174,19 @@ TEST_F(TopShortcutsViewTest, ButtonLayoutSupervisedUserFlow) {
   Layout();
 }
 
+// Settings button is disabled when kSettingsIconDisabled is set.
+TEST_F(TopShortcutsViewTest, DisableSettingsIconPolicy) {
+  const bool enable_settings = true;
+  GetSessionControllerClient()->AddUserSession(
+      "foo@example.com", user_manager::USER_TYPE_REGULAR, enable_settings);
+  SetUpView();
+  EXPECT_EQ(views::Button::STATE_NORMAL, GetSettingsButton()->state());
+
+  local_state()->SetBoolean(prefs::kOsSettingsEnabled, false);
+  EXPECT_EQ(views::Button::STATE_DISABLED, GetSettingsButton()->state());
+
+  local_state()->SetBoolean(prefs::kOsSettingsEnabled, true);
+  EXPECT_EQ(views::Button::STATE_NORMAL, GetSettingsButton()->state());
+}
+
 }  // namespace ash

chrome/browser/chromeos/policy/system_features_disable_list_policy_handler.cc

@@ -4,6 +4,7 @@
 
 #include "system_features_disable_list_policy_handler.h"
 
+#include "ash/public/cpp/ash_pref_names.h"
 #include "base/values.h"
 #include "components/policy/core/common/policy_pref_names.h"
 #include "components/policy/policy_constants.h"
@@ -28,11 +29,16 @@ void SystemFeaturesDisableListPolicyHandler::ApplyList(
     PrefValueMap* prefs) {
   DCHECK(filtered_list.is_list());
   base::Value enums_list(base::Value::Type::LIST);
+  bool os_settings_enabled = true;
   for (const auto& element : filtered_list.GetList()) {
-    enums_list.Append(ConvertToEnum(element.GetString()));
+    SystemFeature feature = ConvertToEnum(element.GetString());
+    enums_list.Append(feature);
+    if (feature == SystemFeature::OS_SETTINGS)
+      os_settings_enabled = false;
   }
   prefs->SetValue(policy_prefs::kSystemFeaturesDisableList,
                   std::move(enums_list));
+  prefs->SetBoolean(ash::prefs::kOsSettingsEnabled, os_settings_enabled);
 }
 
 SystemFeature SystemFeaturesDisableListPolicyHandler::ConvertToEnum(

chrome/test/data/policy/policy_test_cases.json

@@ -3680,7 +3680,8 @@
         "policies": {
           "SystemFeaturesDisableList": ["os_settings"]
         },
-        "prefs": { "policy.system_features_disable_list": { "local_state": true } }
+        "prefs": { "policy.system_features_disable_list": { "local_state": true },
+                   "os_settings_enabled": { "local_state": true } }
       }
     ]
   },