mash: move TriggerAccessibilityAlert to AccessibilityController

changes:
move TriggerAccessibilityAlert from AccessibilityDelegate to
AccessibilityController. This is part of mash work aimed at removing
AccessibilityDelegate.

Bug: 618070
Test: covered by tests
Change-Id: Ic5c026df5a33516e135be5edf38f6fea4cf1d9dc
Reviewed-on: https://chromium-review.googlesource.com/764597
Commit-Queue: Qiang(Joe) Xu <warx@chromium.org>
Reviewed-by: James Cook <jamescook@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Cr-Commit-Position: refs/heads/master@{#516097}

ash/BUILD.gn

@@ -1631,6 +1631,8 @@ static_library("test_support_common") {
   testonly = true
   visibility = [ ":*" ]
   sources = [
+    "accessibility/test_accessibility_controller_client.cc",
+    "accessibility/test_accessibility_controller_client.h",
     "accessibility/test_accessibility_delegate.cc",
     "accessibility/test_accessibility_delegate.h",
     "app_list/test_app_list_presenter_impl.cc",

ash/accelerators/accelerator_controller.cc

@@ -19,7 +19,6 @@
 #include "ash/media_controller.h"
 #include "ash/multi_profile_uma.h"
 #include "ash/new_window_controller.h"
-#include "ash/public/cpp/accessibility_types.h"
 #include "ash/resources/vector_icons/vector_icons.h"
 #include "ash/root_window_controller.h"
 #include "ash/rotator/window_rotation.h"
@@ -1514,8 +1513,8 @@ AcceleratorController::GetAcceleratorProcessingRestriction(int action) const {
   }
   if (Shell::Get()->mru_window_tracker()->BuildMruWindowList().empty() &&
       actions_needing_window_.find(action) != actions_needing_window_.end()) {
-    Shell::Get()->accessibility_delegate()->TriggerAccessibilityAlert(
-        A11Y_ALERT_WINDOW_NEEDED);
+    Shell::Get()->accessibility_controller()->TriggerAccessibilityAlert(
+        mojom::AccessibilityAlert::WINDOW_NEEDED);
     return RESTRICTION_PREVENT_PROCESSING_AND_PROPAGATION;
   }
   return RESTRICTION_NONE;

ash/accelerators/accelerator_controller_unittest.cc

@@ -5,10 +5,11 @@
 #include "ash/accelerators/accelerator_controller.h"
 
 #include "ash/accelerators/accelerator_table.h"
+#include "ash/accessibility/accessibility_controller.h"
 #include "ash/accessibility/accessibility_delegate.h"
+#include "ash/accessibility/test_accessibility_controller_client.h"
 #include "ash/ime/ime_controller.h"
 #include "ash/media_controller.h"
-#include "ash/public/cpp/accessibility_types.h"
 #include "ash/public/cpp/ash_switches.h"
 #include "ash/public/cpp/config.h"
 #include "ash/public/cpp/shell_window_ids.h"
@@ -1196,13 +1197,19 @@ TEST_F(AcceleratorControllerTest, DisallowedAtModalWindow) {
 }
 
 TEST_F(AcceleratorControllerTest, DisallowedWithNoWindow) {
-  AccessibilityDelegate* delegate = Shell::Get()->accessibility_delegate();
+  TestAccessibilityControllerClient client;
+  AccessibilityController* controller =
+      Shell::Get()->accessibility_controller();
+  controller->SetClient(client.CreateInterfacePtrAndBind());
 
   for (size_t i = 0; i < kActionsNeedingWindowLength; ++i) {
-    delegate->TriggerAccessibilityAlert(A11Y_ALERT_NONE);
+    controller->TriggerAccessibilityAlert(mojom::AccessibilityAlert::NONE);
+    controller->FlushMojoForTest();
     EXPECT_TRUE(
         GetController()->PerformActionIfEnabled(kActionsNeedingWindow[i]));
-    EXPECT_EQ(delegate->GetLastAccessibilityAlert(), A11Y_ALERT_WINDOW_NEEDED);
+    controller->FlushMojoForTest();
+    EXPECT_EQ(mojom::AccessibilityAlert::WINDOW_NEEDED,
+              client.last_a11y_alert());
   }
 
   // Make sure we don't alert if we do have a window.
@@ -1210,9 +1217,12 @@ TEST_F(AcceleratorControllerTest, DisallowedWithNoWindow) {
   for (size_t i = 0; i < kActionsNeedingWindowLength; ++i) {
     window.reset(CreateTestWindowInShellWithBounds(gfx::Rect(5, 5, 20, 20)));
     wm::ActivateWindow(window.get());
-    delegate->TriggerAccessibilityAlert(A11Y_ALERT_NONE);
+    controller->TriggerAccessibilityAlert(mojom::AccessibilityAlert::NONE);
+    controller->FlushMojoForTest();
     GetController()->PerformActionIfEnabled(kActionsNeedingWindow[i]);
-    EXPECT_NE(delegate->GetLastAccessibilityAlert(), A11Y_ALERT_WINDOW_NEEDED);
+    controller->FlushMojoForTest();
+    EXPECT_NE(mojom::AccessibilityAlert::WINDOW_NEEDED,
+              client.last_a11y_alert());
   }
 
   // Don't alert if we have a minimized window either.
@@ -1220,9 +1230,12 @@ TEST_F(AcceleratorControllerTest, DisallowedWithNoWindow) {
     window.reset(CreateTestWindowInShellWithBounds(gfx::Rect(5, 5, 20, 20)));
     wm::ActivateWindow(window.get());
     GetController()->PerformActionIfEnabled(WINDOW_MINIMIZE);
-    delegate->TriggerAccessibilityAlert(A11Y_ALERT_NONE);
+    controller->TriggerAccessibilityAlert(mojom::AccessibilityAlert::NONE);
+    controller->FlushMojoForTest();
     GetController()->PerformActionIfEnabled(kActionsNeedingWindow[i]);
-    EXPECT_NE(delegate->GetLastAccessibilityAlert(), A11Y_ALERT_WINDOW_NEEDED);
+    controller->FlushMojoForTest();
+    EXPECT_NE(mojom::AccessibilityAlert::WINDOW_NEEDED,
+              client.last_a11y_alert());
   }
 }
 

ash/accessibility/accessibility_controller.cc

@@ -41,7 +41,7 @@ PrefService* GetActivePrefService() {
 
 AccessibilityController::AccessibilityController(
     service_manager::Connector* connector)
-    : connector_(connector) {
+    : connector_(connector), binding_(this) {
   Shell::Get()->session_controller()->AddObserver(this);
 }
 
@@ -73,6 +73,11 @@ void AccessibilityController::RegisterProfilePrefs(PrefRegistrySimple* registry,
   registry->RegisterForeignPref(prefs::kAccessibilityScreenMagnifierEnabled);
 }
 
+void AccessibilityController::BindRequest(
+    mojom::AccessibilityControllerRequest request) {
+  binding_.Bind(std::move(request));
+}
+
 void AccessibilityController::SetLargeCursorEnabled(bool enabled) {
   PrefService* prefs = GetActivePrefService();
   if (!prefs)
@@ -97,6 +102,17 @@ bool AccessibilityController::IsHighContrastEnabled() const {
   return high_contrast_enabled_;
 }
 
+void AccessibilityController::TriggerAccessibilityAlert(
+    mojom::AccessibilityAlert alert) {
+  if (client_)
+    client_->TriggerAccessibilityAlert(alert);
+}
+
+void AccessibilityController::SetClient(
+    mojom::AccessibilityControllerClientPtr client) {
+  client_ = std::move(client);
+}
+
 void AccessibilityController::OnSigninScreenPrefServiceInitialized(
     PrefService* prefs) {
   ObservePrefs(prefs);
@@ -107,6 +123,10 @@ void AccessibilityController::OnActiveUserPrefServiceChanged(
   ObservePrefs(prefs);
 }
 
+void AccessibilityController::FlushMojoForTest() {
+  client_.FlushForTesting();
+}
+
 void AccessibilityController::ObservePrefs(PrefService* prefs) {
   // Watch for pref updates from webui settings and policy.
   pref_change_registrar_ = std::make_unique<PrefChangeRegistrar>();

ash/accessibility/accessibility_controller.h

@@ -9,8 +9,10 @@
 
 #include "ash/ash_constants.h"
 #include "ash/ash_export.h"
+#include "ash/public/interfaces/accessibility_controller.mojom.h"
 #include "ash/session/session_observer.h"
 #include "base/macros.h"
+#include "mojo/public/cpp/bindings/binding.h"
 
 class PrefChangeRegistrar;
 class PrefRegistrySimple;
@@ -25,7 +27,9 @@ namespace ash {
 // The controller for accessibility features in ash. Features can be enabled
 // in chrome's webui settings or the system tray menu (see TrayAccessibility).
 // Uses preferences to communicate with chrome to support mash.
-class ASH_EXPORT AccessibilityController : public SessionObserver {
+class ASH_EXPORT AccessibilityController
+    : public mojom::AccessibilityController,
+      public SessionObserver {
  public:
   explicit AccessibilityController(service_manager::Connector* connector);
   ~AccessibilityController() override;
@@ -33,16 +37,28 @@ class ASH_EXPORT AccessibilityController : public SessionObserver {
   // See Shell::RegisterProfilePrefs().
   static void RegisterProfilePrefs(PrefRegistrySimple* registry, bool for_test);
 
+  // Binds the mojom::AccessibilityController interface to this object.
+  void BindRequest(mojom::AccessibilityControllerRequest request);
+
   void SetLargeCursorEnabled(bool enabled);
   bool IsLargeCursorEnabled() const;
 
   void SetHighContrastEnabled(bool enabled);
   bool IsHighContrastEnabled() const;
 
+  // Triggers an accessibility alert to give the user feedback.
+  void TriggerAccessibilityAlert(mojom::AccessibilityAlert alert);
+
+  // mojom::AccessibilityController:
+  void SetClient(mojom::AccessibilityControllerClientPtr client) override;
+
   // SessionObserver:
   void OnSigninScreenPrefServiceInitialized(PrefService* prefs) override;
   void OnActiveUserPrefServiceChanged(PrefService* prefs) override;
 
+  // Test helpers:
+  void FlushMojoForTest();
+
  private:
   // Observes either the signin screen prefs or active user prefs and loads
   // initial settings.
@@ -54,6 +70,12 @@ class ASH_EXPORT AccessibilityController : public SessionObserver {
   service_manager::Connector* connector_ = nullptr;
   std::unique_ptr<PrefChangeRegistrar> pref_change_registrar_;
 
+  // Binding for mojom::AccessibilityController interface.
+  mojo::Binding<mojom::AccessibilityController> binding_;
+
+  // Client interface in chrome browser.
+  mojom::AccessibilityControllerClientPtr client_;
+
   bool large_cursor_enabled_ = false;
   int large_cursor_size_in_dip_ = kDefaultLargeCursorSize;
   bool high_contrast_enabled_ = false;

ash/accessibility/accessibility_delegate.h

@@ -110,12 +110,6 @@ class ASH_EXPORT AccessibilityDelegate {
   // is not saved, return a negative value.
   virtual double GetSavedScreenMagnifierScale() = 0;
 
-  // Triggers an accessibility alert to give the user feedback.
-  virtual void TriggerAccessibilityAlert(AccessibilityAlert alert) = 0;
-
-  // Gets the last accessibility alert that was triggered.
-  virtual AccessibilityAlert GetLastAccessibilityAlert() = 0;
-
   // Called when we first detect two fingers are held down, which can be
   // used to toggle spoken feedback on some touch-only devices.
   virtual void OnTwoFingerTouchStart() {}

ash/accessibility/default_accessibility_delegate.cc

@@ -133,15 +133,6 @@ double DefaultAccessibilityDelegate::GetSavedScreenMagnifierScale() {
   return std::numeric_limits<double>::min();
 }
 
-void DefaultAccessibilityDelegate::TriggerAccessibilityAlert(
-    AccessibilityAlert alert) {
-  accessibility_alert_ = alert;
-}
-
-AccessibilityAlert DefaultAccessibilityDelegate::GetLastAccessibilityAlert() {
-  return accessibility_alert_;
-}
-
 bool DefaultAccessibilityDelegate::ShouldToggleSpokenFeedbackViaTouch() {
   return false;
 }

ash/accessibility/default_accessibility_delegate.h

@@ -47,8 +47,6 @@ class ASH_EXPORT DefaultAccessibilityDelegate : public AccessibilityDelegate {
       AccessibilityNotificationVisibility notify) override;
   void SaveScreenMagnifierScale(double scale) override;
   double GetSavedScreenMagnifierScale() override;
-  void TriggerAccessibilityAlert(AccessibilityAlert alert) override;
-  AccessibilityAlert GetLastAccessibilityAlert() override;
   bool ShouldToggleSpokenFeedbackViaTouch() override;
   void PlaySpokenFeedbackToggleCountdown(int tick_count) override;
   void PlayEarcon(int sound_key) override;
@@ -68,7 +66,6 @@ class ASH_EXPORT DefaultAccessibilityDelegate : public AccessibilityDelegate {
   bool tap_dragging_enabled_ = false;
   bool select_to_speak_enabled_ = false;
   bool switch_access_enabled_ = false;
-  AccessibilityAlert accessibility_alert_ = A11Y_ALERT_NONE;
 
   DISALLOW_COPY_AND_ASSIGN(DefaultAccessibilityDelegate);
 };

ash/accessibility/test_accessibility_controller_client.cc

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "ash/accessibility/test_accessibility_controller_client.h"
+
+namespace ash {
+
+TestAccessibilityControllerClient::TestAccessibilityControllerClient()
+    : binding_(this) {}
+
+TestAccessibilityControllerClient::~TestAccessibilityControllerClient() =
+    default;
+
+mojom::AccessibilityControllerClientPtr
+TestAccessibilityControllerClient::CreateInterfacePtrAndBind() {
+  mojom::AccessibilityControllerClientPtr ptr;
+  binding_.Bind(mojo::MakeRequest(&ptr));
+  return ptr;
+}
+
+void TestAccessibilityControllerClient::TriggerAccessibilityAlert(
+    mojom::AccessibilityAlert alert) {
+  last_a11y_alert_ = alert;
+}
+
+}  // namespace ash

ash/accessibility/test_accessibility_controller_client.h

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef ASH_ACCESSIBILITY_TEST_ACCESSIBILITY_CONTROLLER_CLEINT_H_
+#define ASH_ACCESSIBILITY_TEST_ACCESSIBILITY_CONTROLLER_CLEINT_H_
+
+#include "ash/public/interfaces/accessibility_controller.mojom.h"
+#include "base/macros.h"
+#include "mojo/public/cpp/bindings/binding.h"
+
+namespace ash {
+
+// Implement AccessibilityControllerClient mojo interface to simulate chrome
+// behavior in tests. This breaks the ash/chrome dependency to allow testing ash
+// code in isolation.
+class TestAccessibilityControllerClient
+    : public mojom::AccessibilityControllerClient {
+ public:
+  TestAccessibilityControllerClient();
+  ~TestAccessibilityControllerClient() override;
+
+  mojom::AccessibilityControllerClientPtr CreateInterfacePtrAndBind();
+
+  // mojom::AccessibilityControllerClient:
+  void TriggerAccessibilityAlert(mojom::AccessibilityAlert alert) override;
+
+  mojom::AccessibilityAlert last_a11y_alert() const { return last_a11y_alert_; }
+
+ private:
+  mojom::AccessibilityAlert last_a11y_alert_ = mojom::AccessibilityAlert::NONE;
+
+  mojo::Binding<mojom::AccessibilityControllerClient> binding_;
+
+  DISALLOW_COPY_AND_ASSIGN(TestAccessibilityControllerClient);
+};
+
+}  // namespace ash
+
+#endif  // ASH_ACCESSIBILITY_TEST_ACCESSIBILITY_CONTROLLER_CLEINT_H_

ash/mojo_interface_factory.cc

@@ -7,6 +7,7 @@
 #include <utility>
 
 #include "ash/accelerators/accelerator_controller.h"
+#include "ash/accessibility/accessibility_controller.h"
 #include "ash/cast_config_controller.h"
 #include "ash/display/ash_display_controller.h"
 #include "ash/highlighter/highlighter_controller.h"
@@ -47,6 +48,11 @@ void BindAcceleratorControllerRequestOnMainThread(
   Shell::Get()->accelerator_controller()->BindRequest(std::move(request));
 }
 
+void BindAccessibilityControllerRequestOnMainThread(
+    mojom::AccessibilityControllerRequest request) {
+  Shell::Get()->accessibility_controller()->BindRequest(std::move(request));
+}
+
 void BindAppListRequestOnMainThread(
     app_list::mojom::AppListRequest request) {
   Shell::Get()->app_list()->BindRequest(std::move(request));
@@ -154,6 +160,9 @@ void RegisterInterfaces(
   registry->AddInterface(
       base::Bind(&BindAcceleratorControllerRequestOnMainThread),
       main_thread_task_runner);
+  registry->AddInterface(
+      base::Bind(&BindAccessibilityControllerRequestOnMainThread),
+      main_thread_task_runner);
   registry->AddInterface(base::Bind(&BindAppListRequestOnMainThread),
                          main_thread_task_runner);
   registry->AddInterface(

ash/mus/manifest.json

@@ -10,6 +10,7 @@
         "system_ui": [
           "app_list::mojom::AppList",
           "ash::mojom::AcceleratorController",
+          "ash::mojom::AccessibilityController",
           "ash::mojom::AshMessageCenterController",
           "ash::mojom::CastConfig",
           "ash::mojom::HighlighterController",

ash/public/cpp/accessibility_types.h

@@ -12,16 +12,6 @@ enum AccessibilityNotificationVisibility {
   A11Y_NOTIFICATION_SHOW,
 };
 
-enum AccessibilityAlert {
-  A11Y_ALERT_NONE,
-  A11Y_ALERT_CAPS_ON,
-  A11Y_ALERT_CAPS_OFF,
-  A11Y_ALERT_SCREEN_ON,
-  A11Y_ALERT_SCREEN_OFF,
-  A11Y_ALERT_WINDOW_NEEDED,
-  A11Y_ALERT_WINDOW_OVERVIEW_MODE_ENTERED
-};
-
 // Note: Do not change these values; UMA and prefs depend on them.
 enum MagnifierType {
   MAGNIFIER_DISABLED = 0,  // Used by enterprise policy.

ash/public/interfaces/BUILD.gn

@@ -13,6 +13,7 @@ mojom("interfaces_internal") {
 
   sources = [
     "accelerator_controller.mojom",
+    "accessibility_controller.mojom",
     "ash_display_controller.mojom",
     "ash_message_center_controller.mojom",
     "cast_config.mojom",

ash/public/interfaces/accessibility_controller.mojom

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+module ash.mojom;
+
+enum AccessibilityAlert {
+  // Default value, indicates no accessibility alert.
+  NONE,
+
+  // Caps Lock is On.
+  CAPS_ON,
+
+  // Caps Lock is Off.
+  CAPS_OFF,
+
+  // Screen turned on by tablet power button.
+  SCREEN_ON,
+
+  // Screen turned off by tablet power button.
+  SCREEN_OFF,
+
+  // Alerted when no window avaiable and accelerators operated which requires at
+  // least one window.
+  WINDOW_NEEDED,
+
+  // Entered overview mode.
+  WINDOW_OVERVIEW_MODE_ENTERED
+};
+
+// Interface for ash client (e.g. Chrome) to control and query accessibility
+// features.
+interface AccessibilityController {
+  // Sets the client interface.
+  SetClient(AccessibilityControllerClient client);
+};
+
+// Interface for ash to request accessibility service from its client (e.g.
+// Chrome).
+interface AccessibilityControllerClient {
+  // Triggers an accessibility alert to give the user feedback.
+  TriggerAccessibilityAlert(AccessibilityAlert alert);
+};

ash/system/power/power_button_display_controller.cc

@@ -4,7 +4,7 @@
 
 #include "ash/system/power/power_button_display_controller.h"
 
-#include "ash/accessibility/accessibility_delegate.h"
+#include "ash/accessibility/accessibility_controller.h"
 #include "ash/media_controller.h"
 #include "ash/public/cpp/ash_switches.h"
 #include "ash/shell.h"
@@ -69,8 +69,9 @@ void PowerButtonDisplayController::SetDisplayForcedOff(bool forced_off) {
     Shell::Get()->media_controller()->SuspendMediaSessions();
 
   // Send an a11y alert.
-  Shell::Get()->accessibility_delegate()->TriggerAccessibilityAlert(
-      forced_off ? A11Y_ALERT_SCREEN_OFF : A11Y_ALERT_SCREEN_ON);
+  Shell::Get()->accessibility_controller()->TriggerAccessibilityAlert(
+      forced_off ? mojom::AccessibilityAlert::SCREEN_OFF
+                 : mojom::AccessibilityAlert::SCREEN_ON);
 }
 
 void PowerButtonDisplayController::PowerManagerRestarted() {

ash/system/power/tablet_power_button_controller_unittest.cc

@@ -4,6 +4,8 @@
 
 #include "ash/system/power/tablet_power_button_controller.h"
 
+#include "ash/accessibility/accessibility_controller.h"
+#include "ash/accessibility/test_accessibility_controller_client.h"
 #include "ash/media_controller.h"
 #include "ash/public/cpp/ash_switches.h"
 #include "ash/session/session_controller.h"
@@ -637,6 +639,26 @@ TEST_F(TabletPowerButtonControllerTest,
   EXPECT_TRUE(power_manager_client_->backlights_forced_off());
 }
 
+// Tests that a11y alert is sent on tablet power button induced screen state
+// change.
+TEST_F(TabletPowerButtonControllerTest, A11yAlert) {
+  TestAccessibilityControllerClient client;
+  AccessibilityController* controller =
+      Shell::Get()->accessibility_controller();
+  controller->SetClient(client.CreateInterfacePtrAndBind());
+  PressPowerButton();
+  ReleasePowerButton();
+  power_manager_client_->SendBrightnessChanged(0, true);
+  controller->FlushMojoForTest();
+  EXPECT_EQ(mojom::AccessibilityAlert::SCREEN_OFF, client.last_a11y_alert());
+
+  PressPowerButton();
+  power_manager_client_->SendBrightnessChanged(kNonZeroBrightness, true);
+  controller->FlushMojoForTest();
+  EXPECT_EQ(mojom::AccessibilityAlert::SCREEN_ON, client.last_a11y_alert());
+  ReleasePowerButton();
+}
+
 using NoTabletModePowerButtonControllerTest = NoTabletModePowerButtonTestBase;
 
 // Tests that tablet power button behavior should not be enabled on the device

ash/system/tray_caps_lock.cc

@@ -6,7 +6,7 @@
 
 #include <memory>
 
-#include "ash/accessibility/accessibility_delegate.h"
+#include "ash/accessibility/accessibility_controller.h"
 #include "ash/ime/ime_controller.h"
 #include "ash/metrics/user_metrics_recorder.h"
 #include "ash/public/cpp/config.h"
@@ -222,8 +222,9 @@ void TrayCapsLock::OnCapsLockChanged(bool enabled) {
   caps_lock_enabled_ = enabled;
 
   // Send an a11y alert.
-  Shell::Get()->accessibility_delegate()->TriggerAccessibilityAlert(
-      enabled ? A11Y_ALERT_CAPS_ON : A11Y_ALERT_CAPS_OFF);
+  Shell::Get()->accessibility_controller()->TriggerAccessibilityAlert(
+      enabled ? mojom::AccessibilityAlert::CAPS_ON
+              : mojom::AccessibilityAlert::CAPS_OFF);
 
   if (tray_view())
     tray_view()->SetVisible(caps_lock_enabled_);

ash/system/tray_caps_lock_unittest.cc

@@ -4,14 +4,34 @@
 
 #include "ash/system/tray_caps_lock.h"
 
+#include "ash/accessibility/accessibility_controller.h"
+#include "ash/accessibility/test_accessibility_controller_client.h"
+#include "ash/shell.h"
 #include "ash/system/tray/system_tray.h"
 #include "ash/system/tray/system_tray_test_api.h"
+#include "ash/system/web_notification/web_notification_tray.h"
 #include "ash/test/ash_test_base.h"
 
 namespace ash {
-namespace {
 
-using TrayCapsLockTest = AshTestBase;
+class TrayCapsLockTest : public AshTestBase {
+ public:
+  TrayCapsLockTest() = default;
+  ~TrayCapsLockTest() override = default;
+
+  void SetUp() override {
+    AshTestBase::SetUp();
+    WebNotificationTray::DisableAnimationsForTest(true);
+  }
+
+  void TearDown() override {
+    WebNotificationTray::DisableAnimationsForTest(false);
+    AshTestBase::TearDown();
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(TrayCapsLockTest);
+};
 
 // Tests that the icon becomes visible when the tray controller toggles it.
 TEST_F(TrayCapsLockTest, Visibility) {
@@ -30,5 +50,25 @@ TEST_F(TrayCapsLockTest, Visibility) {
   EXPECT_FALSE(caps_lock->tray_view()->visible());
 }
 
-}  // namespace
+// Tests that a11y alert is sent on toggling caps lock.
+TEST_F(TrayCapsLockTest, A11yAlert) {
+  SystemTray* tray = GetPrimarySystemTray();
+  TrayCapsLock* caps_lock = SystemTrayTestApi(tray).tray_caps_lock();
+
+  TestAccessibilityControllerClient client;
+  AccessibilityController* controller =
+      Shell::Get()->accessibility_controller();
+  controller->SetClient(client.CreateInterfacePtrAndBind());
+
+  // Simulate turning on caps lock.
+  caps_lock->OnCapsLockChanged(true);
+  controller->FlushMojoForTest();
+  EXPECT_EQ(mojom::AccessibilityAlert::CAPS_ON, client.last_a11y_alert());
+
+  // Simulate turning off caps lock.
+  caps_lock->OnCapsLockChanged(false);
+  controller->FlushMojoForTest();
+  EXPECT_EQ(mojom::AccessibilityAlert::CAPS_OFF, client.last_a11y_alert());
+}
+
 }  // namespace ash

ash/wm/overview/window_selector.cc

@@ -11,9 +11,8 @@
 #include <utility>
 #include <vector>
 
-#include "ash/accessibility/accessibility_delegate.h"
+#include "ash/accessibility/accessibility_controller.h"
 #include "ash/metrics/user_metrics_recorder.h"
-#include "ash/public/cpp/accessibility_types.h"
 #include "ash/public/cpp/shell_window_ids.h"
 #include "ash/screen_util.h"
 #include "ash/shelf/shelf.h"
@@ -315,8 +314,8 @@ void WindowSelector::Init(const WindowList& windows,
   display::Screen::GetScreen()->AddObserver(this);
   base::RecordAction(base::UserMetricsAction("WindowSelector_Overview"));
   // Send an a11y alert.
-  Shell::Get()->accessibility_delegate()->TriggerAccessibilityAlert(
-      A11Y_ALERT_WINDOW_OVERVIEW_MODE_ENTERED);
+  Shell::Get()->accessibility_controller()->TriggerAccessibilityAlert(
+      mojom::AccessibilityAlert::WINDOW_OVERVIEW_MODE_ENTERED);
 
   UpdateShelfVisibility();
 }

ash/wm/overview/window_selector_unittest.cc

@@ -6,12 +6,12 @@
 #include <memory>
 #include <vector>
 
-#include "ash/accessibility/accessibility_delegate.h"
+#include "ash/accessibility/accessibility_controller.h"
+#include "ash/accessibility/test_accessibility_controller_client.h"
 #include "ash/app_list/test_app_list_presenter_impl.h"
 #include "ash/display/screen_orientation_controller_chromeos.h"
 #include "ash/display/screen_orientation_controller_test_api.h"