Move SessionObserver to ash/public

so that CL like this (crrev.com/c/2214761) can use it.

Bug: None
Change-Id: I685819c89b87603a542324431ba0a6d9a80eb1e5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2283504
Commit-Queue: Mitsuru Oshima <oshima@chromium.org>
Reviewed-by: Toni Baržić <tbarzic@chromium.org>
Cr-Commit-Position: refs/heads/master@{#785832}

ash/BUILD.gn

@@ -647,8 +647,6 @@ component("ash") {
     "session/session_activation_observer_holder.h",
     "session/session_controller_impl.cc",
     "session/session_controller_impl.h",
-    "session/session_observer.cc",
-    "session/session_observer.h",
     "session/teleport_warning_dialog.cc",
     "session/teleport_warning_dialog.h",
     "shelf/assistant_overlay.cc",

ash/accessibility/accessibility_controller_impl.cc

@@ -24,10 +24,10 @@
 #include "ash/public/cpp/ash_constants.h"
 #include "ash/public/cpp/ash_pref_names.h"
 #include "ash/public/cpp/notification_utils.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/public/cpp/shell_window_ids.h"
 #include "ash/resources/vector_icons/vector_icons.h"
 #include "ash/session/session_controller_impl.h"
-#include "ash/session/session_observer.h"
 #include "ash/shell.h"
 #include "ash/sticky_keys/sticky_keys_controller.h"
 #include "ash/strings/grit/ash_strings.h"

ash/accessibility/accessibility_controller_impl.h

@@ -10,8 +10,8 @@
 #include "ash/ash_export.h"
 #include "ash/public/cpp/accessibility_controller.h"
 #include "ash/public/cpp/ash_constants.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/public/cpp/tablet_mode_observer.h"
-#include "ash/session/session_observer.h"
 #include "base/callback_forward.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"

ash/ambient/ambient_controller.h

@@ -14,7 +14,7 @@
 #include "ash/ambient/ui/ambient_view_delegate.h"
 #include "ash/ash_export.h"
 #include "ash/public/cpp/ambient/ambient_ui_model.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/system/power/power_status.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"

ash/app_list/app_list_controller_impl.h

@@ -23,10 +23,10 @@
 #include "ash/public/cpp/app_list/app_list_controller.h"
 #include "ash/public/cpp/assistant/controller/assistant_controller_observer.h"
 #include "ash/public/cpp/keyboard/keyboard_controller_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/public/cpp/shelf_types.h"
 #include "ash/public/cpp/tablet_mode_observer.h"
 #include "ash/public/cpp/wallpaper_controller_observer.h"
-#include "ash/session/session_observer.h"
 #include "ash/shelf/shelf_layout_manager.h"
 #include "ash/shell_observer.h"
 #include "ash/wm/mru_window_tracker.h"

ash/assistant/assistant_state_controller.h

@@ -7,7 +7,7 @@
 
 #include "ash/ash_export.h"
 #include "ash/public/cpp/assistant/assistant_state.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "base/macros.h"
 
 namespace ash {

ash/detachable_base/detachable_base_notification_controller.h

@@ -8,7 +8,7 @@
 #include "ash/ash_export.h"
 #include "ash/detachable_base/detachable_base_handler.h"
 #include "ash/detachable_base/detachable_base_observer.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "base/scoped_observer.h"
 
 namespace ash {

ash/display/display_alignment_controller.h

@@ -9,7 +9,7 @@
 
 #include "ash/ash_export.h"
 #include "ash/display/window_tree_host_manager.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "base/containers/flat_map.h"
 #include "ui/events/event_handler.h"
 

ash/display/display_highlight_controller.h

@@ -7,7 +7,7 @@
 
 #include "ash/ash_export.h"
 #include "ash/display/window_tree_host_manager.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ui/views/widget/widget.h"
 
 namespace ash {

ash/display/display_prefs.h

@@ -9,7 +9,7 @@
 #include <array>
 
 #include "ash/ash_export.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "base/optional.h"
 #include "third_party/cros_system_api/dbus/service_constants.h"
 #include "ui/display/display.h"

ash/display/display_shutdown_observer.h

@@ -5,7 +5,7 @@
 #ifndef ASH_DISPLAY_DISPLAY_SHUTDOWN_OBSERVER_H_
 #define ASH_DISPLAY_DISPLAY_SHUTDOWN_OBSERVER_H_
 
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "base/macros.h"
 
 namespace display {

ash/display/privacy_screen_controller.h

@@ -8,7 +8,7 @@
 #include <memory>
 
 #include "ash/ash_export.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "base/observer_list.h"
 #include "ui/display/manager/display_configurator.h"
 

ash/first_run/first_run_helper_impl.h

@@ -7,7 +7,7 @@
 
 #include "ash/ash_export.h"
 #include "ash/public/cpp/first_run_helper.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "base/callback.h"
 #include "base/macros.h"
 

ash/keyboard/keyboard_controller_impl.h

@@ -14,7 +14,7 @@
 #include "ash/keyboard/ui/keyboard_ui_controller.h"
 #include "ash/public/cpp/keyboard/keyboard_controller.h"
 #include "ash/public/cpp/keyboard/keyboard_controller_observer.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "base/macros.h"
 #include "base/optional.h"
 #include "base/time/time.h"

ash/keyboard/virtual_keyboard_controller.h

@@ -10,8 +10,8 @@
 #include "ash/ash_export.h"
 #include "ash/bluetooth_devices_observer.h"
 #include "ash/public/cpp/keyboard/keyboard_controller_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/public/cpp/tablet_mode_observer.h"
-#include "ash/session/session_observer.h"
 #include "base/macros.h"
 #include "ui/base/ime/chromeos/ime_keyset.h"
 #include "ui/events/devices/input_device_event_observer.h"

ash/login/ui/lock_screen.h

@@ -7,7 +7,7 @@
 
 #include "ash/ash_export.h"
 #include "ash/public/cpp/login_types.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/tray_action/tray_action.h"
 #include "ash/tray_action/tray_action_observer.h"
 #include "base/macros.h"

ash/magnifier/docked_magnifier_controller_impl.h

@@ -10,7 +10,7 @@
 #include "ash/ash_export.h"
 #include "ash/display/window_tree_host_manager.h"
 #include "ash/public/cpp/docked_magnifier_controller.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ui/base/ime/ime_bridge_observer.h"
 #include "ui/base/ime/input_method_observer.h"
 #include "ui/events/event_handler.h"

ash/media/media_notification_controller_impl.cc

@@ -7,8 +7,8 @@
 #include "ash/media/media_notification_constants.h"
 #include "ash/media/media_notification_container_impl.h"
 #include "ash/public/cpp/notification_utils.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/session/session_controller_impl.h"
-#include "ash/session/session_observer.h"
 #include "ash/shell.h"
 #include "ash/shell_delegate.h"
 #include "base/bind.h"

ash/multi_device_setup/multi_device_notification_presenter.h

@@ -9,7 +9,7 @@
 #include <string>
 
 #include "ash/ash_export.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "base/callback.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"

ash/multi_user/multi_user_window_manager_impl.h

@@ -10,8 +10,8 @@
 
 #include "ash/ash_export.h"
 #include "ash/public/cpp/multi_user_window_manager.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/public/cpp/tablet_mode_observer.h"
-#include "ash/session/session_observer.h"
 #include "base/containers/flat_map.h"
 #include "base/macros.h"
 #include "base/observer_list.h"

ash/policy/policy_recommendation_restorer.h

@@ -9,7 +9,7 @@
 #include <set>
 #include <string>
 
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "base/macros.h"
 #include "base/timer/timer.h"
 #include "ui/base/user_activity/user_activity_observer.h"

ash/public/cpp/BUILD.gn

@@ -219,6 +219,8 @@ component("cpp") {
     "session/session_controller.cc",
     "session/session_controller.h",
     "session/session_controller_client.h",
+    "session/session_observer.cc",
+    "session/session_observer.h",
     "session/session_types.cc",
     "session/session_types.h",
     "session/user_info.cc",

ash/public/cpp/session/session_controller.h

@@ -19,6 +19,7 @@ class AccountId;
 
 namespace ash {
 
+class SessionObserver;
 class SessionControllerClient;
 class SessionActivationObserver;
 
@@ -115,6 +116,10 @@ class ASH_PUBLIC_EXPORT SessionController {
       const AccountId& account_id,
       SessionActivationObserver* observer) = 0;
 
+  // Adds/remove session observer.
+  virtual void AddObserver(SessionObserver* observer) = 0;
+  virtual void RemoveObserver(SessionObserver* observer) = 0;
+
  protected:
   SessionController();
   virtual ~SessionController();

ash/session/session_observer.cc → ash/public/cpp/session/session_observer.cc

@@ -2,22 +2,21 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 
-#include "ash/session/session_controller_impl.h"
-#include "ash/shell.h"
+#include "ash/public/cpp/session/session_controller.h"
 
 namespace ash {
 
 ScopedSessionObserver::ScopedSessionObserver(SessionObserver* observer)
     : observer_(observer) {
-  DCHECK(Shell::HasInstance());
-  Shell::Get()->session_controller()->AddObserver(observer_);
+  DCHECK(SessionController::Get());
+  SessionController::Get()->AddObserver(observer_);
 }
 
 ScopedSessionObserver::~ScopedSessionObserver() {
-  DCHECK(Shell::HasInstance());
-  Shell::Get()->session_controller()->RemoveObserver(observer_);
+  DCHECK(SessionController::Get());
+  SessionController::Get()->RemoveObserver(observer_);
 }
 
 }  // namespace ash

ash/session/session_observer.h → ash/public/cpp/session/session_observer.h

@@ -2,10 +2,10 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef ASH_SESSION_SESSION_OBSERVER_H_
-#define ASH_SESSION_SESSION_OBSERVER_H_
+#ifndef ASH_PUBLIC_CPP_SESSION_SESSION_OBSERVER_H_
+#define ASH_PUBLIC_CPP_SESSION_SESSION_OBSERVER_H_
 
-#include "ash/ash_export.h"
+#include "ash/public/cpp/ash_public_export.h"
 #include "base/macros.h"
 #include "base/observer_list_types.h"
 #include "components/session_manager/session_manager_types.h"
@@ -17,7 +17,7 @@ namespace ash {
 
 enum class LoginStatus;
 
-class ASH_EXPORT SessionObserver : public base::CheckedObserver {
+class ASH_PUBLIC_EXPORT SessionObserver : public base::CheckedObserver {
  public:
   // Called when the active user session has changed.
   virtual void OnActiveUserSessionChanged(const AccountId& account_id) {}
@@ -64,7 +64,7 @@ class ASH_EXPORT SessionObserver : public base::CheckedObserver {
 //
 // NOTE: Both ash::Shell and ash::SessionControllerImpl must outlive your
 // object. You may find it clearer to manually add and remove your observer.
-class ASH_EXPORT ScopedSessionObserver {
+class ASH_PUBLIC_EXPORT ScopedSessionObserver {
  public:
   explicit ScopedSessionObserver(SessionObserver* observer);
   virtual ~ScopedSessionObserver();
@@ -77,4 +77,4 @@ class ASH_EXPORT ScopedSessionObserver {
 
 }  // namespace ash
 
-#endif  // ASH_SESSION_SESSION_OBSERVER_H_
+#endif  // ASH_PUBLIC_CPP_SESSION_SESSION_OBSERVER_H_

ash/session/session_controller_impl.cc

@@ -12,11 +12,11 @@
 #include "ash/metrics/user_metrics_recorder.h"
 #include "ash/public/cpp/session/session_activation_observer.h"
 #include "ash/public/cpp/session/session_controller_client.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/public/cpp/session/user_info.h"
 #include "ash/session/fullscreen_controller.h"
 #include "ash/session/multiprofiles_intro_dialog.h"
 #include "ash/session/session_aborted_dialog.h"
-#include "ash/session/session_observer.h"
 #include "ash/session/teleport_warning_dialog.h"
 #include "ash/shell.h"
 #include "ash/system/power/power_event_observer.h"

ash/session/session_controller_impl.h

@@ -174,9 +174,6 @@ class ASH_EXPORT SessionControllerImpl : public SessionController {
   // the active user profile prefs. Returns null early during startup.
   PrefService* GetActivePrefService() const;
 
-  void AddObserver(SessionObserver* observer);
-  void RemoveObserver(SessionObserver* observer);
-
   // Returns the ash notion of login status.
   // NOTE: Prefer GetSessionState() in new code because the concept of
   // SessionState more closes matches the state in chrome.
@@ -208,6 +205,8 @@ class ASH_EXPORT SessionControllerImpl : public SessionController {
   void RemoveSessionActivationObserverForAccountId(
       const AccountId& account_id,
       SessionActivationObserver* observer) override;
+  void AddObserver(SessionObserver* observer) override;
+  void RemoveObserver(SessionObserver* observer) override;
 
   // Test helpers.
   void ClearUserSessionsForTest();

ash/session/session_controller_impl_unittest.cc

@@ -11,7 +11,7 @@
 
 #include "ash/login_status.h"
 #include "ash/public/cpp/ash_prefs.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/session/test_session_controller_client.h"
 #include "ash/shell.h"
 #include "ash/system/tray/system_tray_notifier.h"

ash/shelf/shelf_controller.h

@@ -10,9 +10,9 @@
 
 #include "ash/ash_export.h"
 #include "ash/display/window_tree_host_manager.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/public/cpp/shelf_model.h"
 #include "ash/public/cpp/tablet_mode_observer.h"
-#include "ash/session/session_observer.h"
 #include "base/scoped_observer.h"
 #include "ui/message_center/message_center.h"
 #include "ui/message_center/message_center_observer.h"

ash/shelf/shelf_layout_manager.h

@@ -10,12 +10,12 @@
 #include "ash/ash_export.h"
 #include "ash/home_screen/drag_window_from_shelf_controller.h"
 #include "ash/public/cpp/app_list/app_list_controller_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/public/cpp/shelf_config.h"
 #include "ash/public/cpp/shelf_types.h"
 #include "ash/public/cpp/tablet_mode_observer.h"
 #include "ash/public/cpp/wallpaper_controller.h"
 #include "ash/public/cpp/wallpaper_controller_observer.h"
-#include "ash/session/session_observer.h"
 #include "ash/shelf/shelf.h"
 #include "ash/shelf/shelf_metrics.h"
 #include "ash/shelf/shelf_widget.h"

ash/shelf/shelf_locking_manager.h

@@ -6,8 +6,8 @@
 #define ASH_SHELF_SHELF_LOCKING_MANAGER_H_
 
 #include "ash/ash_export.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/public/cpp/shelf_types.h"
-#include "ash/session/session_observer.h"
 #include "ash/wm/lock_state_observer.h"
 
 namespace ash {

ash/shelf/shelf_widget.h

@@ -9,8 +9,8 @@
 
 #include "ash/accessibility/accessibility_observer.h"
 #include "ash/ash_export.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/public/cpp/shelf_types.h"
-#include "ash/session/session_observer.h"
 #include "ash/shelf/contextual_tooltip.h"
 #include "ash/shelf/hotseat_transition_animator.h"
 #include "ash/shelf/hotseat_widget.h"

ash/shell.h

@@ -11,8 +11,8 @@
 
 #include "ash/ash_export.h"
 #include "ash/metrics/user_metrics_recorder.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/public/cpp/shelf_types.h"
-#include "ash/session/session_observer.h"
 #include "ash/wm/system_modal_container_event_filter_delegate.h"
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"

ash/system/accessibility/dictation_button_tray.h

@@ -8,7 +8,7 @@
 #include "ash/accelerators/accelerator_controller_impl.h"
 #include "ash/accessibility/accessibility_observer.h"
 #include "ash/ash_export.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/shell_observer.h"
 #include "ash/system/tray/tray_background_view.h"
 #include "base/macros.h"

ash/system/accessibility/select_to_speak_tray.h

@@ -7,7 +7,7 @@
 
 #include "ash/accessibility/accessibility_observer.h"
 #include "ash/ash_export.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/system/tray/tray_background_view.h"
 #include "base/macros.h"
 #include "ui/views/controls/image_view.h"

ash/system/accessibility/tray_accessibility.h

@@ -9,7 +9,7 @@
 
 #include "ash/accessibility/accessibility_delegate.h"
 #include "ash/accessibility/accessibility_observer.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/system/tray/tray_detailed_view.h"
 #include "base/macros.h"
 #include "ui/gfx/font.h"

ash/system/bluetooth/bluetooth_power_controller.h

@@ -6,7 +6,7 @@
 #define ASH_SYSTEM_BLUETOOTH_BLUETOOTH_POWER_CONTROLLER_H_
 
 #include "ash/ash_export.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "base/containers/queue.h"
 #include "base/macros.h"
 #include "components/prefs/pref_change_registrar.h"

ash/system/gesture_education/gesture_education_notification_controller.h

@@ -6,8 +6,8 @@
 #define ASH_SYSTEM_GESTURE_EDUCATION_GESTURE_EDUCATION_NOTIFICATION_CONTROLLER_H_
 
 #include "ash/ash_export.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/public/cpp/tablet_mode_observer.h"
-#include "ash/session/session_observer.h"
 #include "ash/wm/tablet_mode/tablet_mode_controller.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"

ash/system/message_center/ash_message_center_lock_screen_controller.h

@@ -6,7 +6,7 @@
 #define ASH_SYSTEM_MESSAGE_CENTER_ASH_MESSAGE_CENTER_LOCK_SCREEN_CONTROLLER_H_
 
 #include "ash/ash_export.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "base/optional.h"
 #include "components/account_id/account_id.h"
 #include "ui/message_center/lock_screen/lock_screen_controller.h"

ash/system/message_center/inactive_user_notification_blocker.h

@@ -8,7 +8,7 @@
 #include <map>
 
 #include "ash/ash_export.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "base/macros.h"
 #include "components/account_id/account_id.h"
 #include "ui/message_center/notification_blocker.h"

ash/system/message_center/message_center_controller.h

@@ -9,7 +9,7 @@
 
 #include "ash/ash_export.h"
 #include "ash/public/cpp/message_center/arc_notifications_host_initializer.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "base/macros.h"
 #include "base/observer_list.h"
 #include "mojo/public/cpp/bindings/pending_remote.h"

ash/system/message_center/session_state_notification_blocker.h

@@ -6,7 +6,7 @@
 #define ASH_SYSTEM_MESSAGE_CENTER_SESSION_STATE_NOTIFICATION_BLOCKER_H_
 
 #include "ash/ash_export.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "base/macros.h"
 #include "ui/message_center/notification_blocker.h"
 

ash/system/model/session_length_limit_model.h

@@ -5,7 +5,7 @@
 #ifndef ASH_SYSTEM_MODEL_SESSION_LENGTH_LIMIT_MODEL_H_
 #define ASH_SYSTEM_MODEL_SESSION_LENGTH_LIMIT_MODEL_H_
 
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "base/observer_list.h"
 #include "base/time/time.h"
 #include "base/timer/timer.h"

ash/system/network/network_tray_view.h

@@ -7,7 +7,7 @@
 
 #include <memory>
 
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/system/network/active_network_icon.h"
 #include "ash/system/network/network_icon_animation_observer.h"
 #include "ash/system/network/tray_network_state_observer.h"

ash/system/night_light/night_light_controller_impl.h

@@ -10,7 +10,7 @@
 #include "ash/ash_export.h"
 #include "ash/display/window_tree_host_manager.h"
 #include "ash/public/cpp/night_light_controller.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/system/night_light/time_of_day.h"
 #include "base/containers/flat_map.h"
 #include "base/memory/weak_ptr.h"

ash/system/overview/overview_button_tray.h

@@ -6,9 +6,9 @@
 #define ASH_SYSTEM_OVERVIEW_OVERVIEW_BUTTON_TRAY_H_
 
 #include "ash/ash_export.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/public/cpp/shelf_config.h"
 #include "ash/public/cpp/tablet_mode_observer.h"
-#include "ash/session/session_observer.h"
 #include "ash/system/tray/tray_background_view.h"
 #include "ash/wm/overview/overview_observer.h"
 #include "base/macros.h"

ash/system/palette/palette_tray.h

@@ -8,7 +8,7 @@
 #include <memory>
 
 #include "ash/ash_export.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/shell_observer.h"
 #include "ash/system/palette/palette_tool_manager.h"
 #include "ash/system/tray/tray_background_view.h"

ash/system/palette/palette_welcome_bubble.h

@@ -6,7 +6,7 @@
 #define ASH_SYSTEM_PALETTE_PALETTE_WELCOME_BUBBLE_H_
 
 #include "ash/ash_export.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "base/macros.h"
 #include "ui/events/event_handler.h"
 #include "ui/views/widget/widget_observer.h"

ash/system/power/power_event_observer.h

@@ -8,7 +8,7 @@
 #include <memory>
 
 #include "ash/ash_export.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "base/unguessable_token.h"

ash/system/power/power_prefs.h

@@ -8,7 +8,7 @@
 #include <memory>
 
 #include "ash/ash_export.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "base/macros.h"
 #include "base/scoped_observer.h"
 #include "base/time/tick_clock.h"

ash/system/power/tray_power.h

@@ -7,7 +7,7 @@
 
 #include <memory>
 
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/system/power/power_status.h"
 #include "ash/system/tray/tray_item_view.h"
 #include "base/macros.h"

ash/system/power/video_activity_notifier.h

@@ -6,7 +6,7 @@
 #define ASH_SYSTEM_POWER_VIDEO_ACTIVITY_NOTIFIER_H_
 
 #include "ash/ash_export.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/wm/video_detector.h"
 #include "base/compiler_specific.h"
 #include "base/macros.h"

ash/system/session/logout_button_tray.h

@@ -8,7 +8,7 @@
 #include <memory>
 
 #include "ash/ash_export.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/system/tray/tray_background_view.h"
 #include "base/macros.h"
 #include "base/time/time.h"

ash/system/session/logout_confirmation_controller.h

@@ -8,7 +8,7 @@
 #include <memory>
 
 #include "ash/ash_export.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "base/callback_forward.h"
 #include "base/macros.h"
 #include "base/time/time.h"

ash/system/session/session_limit_notification_controller.h

@@ -5,6 +5,7 @@
 #ifndef ASH_SYSTEM_SESSION_SESSION_LIMIT_NOTIFICATION_CONTROLLER_H_
 #define ASH_SYSTEM_SESSION_SESSION_LIMIT_NOTIFICATION_CONTROLLER_H_
 
+#include "ash/ash_export.h"
 #include "ash/system/model/session_length_limit_model.h"
 
 namespace ash {

ash/system/status_area_widget.h

@@ -7,8 +7,8 @@
 
 #include "ash/ash_export.h"
 #include "ash/login_status.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/public/cpp/shelf_types.h"
-#include "ash/session/session_observer.h"
 #include "ash/shelf/shelf_component.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"

ash/system/supervised/supervised_notification_controller.h

@@ -8,7 +8,7 @@
 #include <string>
 
 #include "ash/ash_export.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "base/strings/string16.h"
 
 namespace ash {

ash/system/time/time_tray_item_view.h

@@ -6,7 +6,7 @@
 #define ASH_SYSTEM_TIME_TIME_TRAY_ITEM_VIEW_H_
 
 #include "ash/ash_export.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/system/tray/tray_item_view.h"
 #include "base/macros.h"
 

ash/system/toast/toast_manager_impl.h

@@ -9,9 +9,9 @@
 #include <string>
 
 #include "ash/ash_export.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/public/cpp/toast_data.h"
 #include "ash/public/cpp/toast_manager.h"
-#include "ash/session/session_observer.h"
 #include "ash/system/toast/toast_overlay.h"
 #include "base/containers/circular_deque.h"
 #include "base/memory/weak_ptr.h"

ash/system/unified/ime_mode_view.h

@@ -5,8 +5,8 @@
 #ifndef ASH_SYSTEM_UNIFIED_IME_MODE_VIEW_H_
 #define ASH_SYSTEM_UNIFIED_IME_MODE_VIEW_H_
 
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/public/cpp/tablet_mode_observer.h"
-#include "ash/session/session_observer.h"
 #include "ash/system/ime/ime_observer.h"
 #include "ash/system/model/locale_model.h"
 #include "ash/system/tray/tray_item_view.h"

ash/system/unified/managed_device_tray_item_view.h

@@ -5,7 +5,7 @@
 #ifndef ASH_SYSTEM_UNIFIED_MANAGED_DEVICE_TRAY_ITEM_VIEW_H_
 #define ASH_SYSTEM_UNIFIED_MANAGED_DEVICE_TRAY_ITEM_VIEW_H_
 
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/system/enterprise/enterprise_domain_observer.h"
 #include "ash/system/tray/tray_item_view.h"
 #include "base/macros.h"

ash/system/unified/notification_counter_view.h

@@ -5,7 +5,7 @@
 #ifndef ASH_SYSTEM_UNIFIED_NOTIFICATION_COUNTER_VIEW_H_
 #define ASH_SYSTEM_UNIFIED_NOTIFICATION_COUNTER_VIEW_H_
 
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/system/tray/tray_item_view.h"
 #include "base/macros.h"
 

ash/system/unified/unified_managed_device_view.h

@@ -5,7 +5,8 @@
 #ifndef ASH_SYSTEM_UNIFIED_UNIFIED_MANAGED_DEVICE_VIEW_H_
 #define ASH_SYSTEM_UNIFIED_UNIFIED_MANAGED_DEVICE_VIEW_H_
 
-#include "ash/session/session_observer.h"
+#include "ash/ash_export.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/system/enterprise/enterprise_domain_observer.h"
 #include "base/macros.h"
 #include "ui/views/view.h"

ash/system/unified/unified_system_info_view.cc

@@ -6,9 +6,9 @@
 
 #include "ash/public/cpp/ash_features.h"
 #include "ash/public/cpp/ash_view_ids.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/resources/vector_icons/vector_icons.h"
 #include "ash/session/session_controller_impl.h"
-#include "ash/session/session_observer.h"
 #include "ash/shell.h"
 #include "ash/strings/grit/ash_strings.h"
 #include "ash/style/ash_color_provider.h"

ash/system/virtual_keyboard/virtual_keyboard_tray.h

@@ -7,7 +7,7 @@
 
 #include "ash/accessibility/accessibility_observer.h"
 #include "ash/public/cpp/keyboard/keyboard_controller_observer.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/shell_observer.h"
 #include "ash/system/tray/tray_background_view.h"
 #include "base/macros.h"

ash/touch/touch_devices_controller.h

@@ -8,7 +8,7 @@
 #include <memory>
 
 #include "ash/ash_export.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "base/callback.h"
 
 class AccountId;

ash/wallpaper/wallpaper_controller_impl.h

@@ -13,11 +13,11 @@
 
 #include "ash/ash_export.h"
 #include "ash/display/window_tree_host_manager.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/public/cpp/tablet_mode_observer.h"
 #include "ash/public/cpp/wallpaper_controller.h"
 #include "ash/public/cpp/wallpaper_info.h"
 #include "ash/public/cpp/wallpaper_types.h"
-#include "ash/session/session_observer.h"
 #include "ash/shell_observer.h"
 #include "ash/wallpaper/wallpaper_utils/wallpaper_color_calculator_observer.h"
 #include "ash/wallpaper/wallpaper_utils/wallpaper_resizer_observer.h"

ash/wm/desks/desks_controller.h

@@ -11,7 +11,7 @@
 
 #include "ash/ash_export.h"
 #include "ash/public/cpp/desks_helper.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/wm/desks/desks_histogram_enums.h"
 #include "ash/wm/desks/root_window_desk_switch_animator.h"
 #include "base/containers/flat_map.h"

ash/wm/gestures/back_gesture/back_gesture_contextual_nudge_controller_impl.h

@@ -7,9 +7,9 @@
 
 #include "ash/ash_export.h"
 #include "ash/public/cpp/back_gesture_contextual_nudge_controller.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/public/cpp/shelf_config.h"
 #include "ash/public/cpp/tablet_mode_observer.h"
-#include "ash/session/session_observer.h"
 #include "ash/wm/tablet_mode/tablet_mode_controller.h"
 #include "base/memory/weak_ptr.h"
 #include "base/scoped_observer.h"

ash/wm/lock_state_controller.h

@@ -8,7 +8,7 @@
 #include <memory>
 
 #include "ash/ash_export.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/shutdown_reason.h"
 #include "ash/wallpaper/wallpaper_property.h"
 #include "ash/wm/lock_state_observer.h"

ash/wm/overlay_event_filter.h

@@ -6,7 +6,7 @@
 #define ASH_WM_OVERLAY_EVENT_FILTER_H_
 
 #include "ash/ash_export.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "ui/aura/window.h"

ash/wm/tablet_mode/tablet_mode_controller.h

@@ -12,8 +12,8 @@
 #include "ash/ash_export.h"
 #include "ash/bluetooth_devices_observer.h"
 #include "ash/display/window_tree_host_manager.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/public/cpp/tablet_mode.h"
-#include "ash/session/session_observer.h"
 #include "ash/shell_observer.h"
 #include "base/compiler_specific.h"
 #include "base/macros.h"

ash/wm/tablet_mode/tablet_mode_window_manager.h

@@ -12,7 +12,7 @@
 #include <vector>
 
 #include "ash/ash_export.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/wm/mru_window_tracker.h"
 #include "ash/wm/overview/overview_observer.h"
 #include "ash/wm/splitview/split_view_controller.h"

ash/wm/video_detector.h

@@ -10,7 +10,7 @@
 #include <set>
 
 #include "ash/ash_export.h"
-#include "ash/session/session_observer.h"
+#include "ash/public/cpp/session/session_observer.h"
 #include "ash/shell_observer.h"
 #include "base/compiler_specific.h"
 #include "base/macros.h"

chrome/browser/ui/ash/test_session_controller.cc

@@ -76,3 +76,7 @@ void TestSessionController::AddSessionActivationObserverForAccountId(
 void TestSessionController::RemoveSessionActivationObserverForAccountId(
     const AccountId& account_id,
     ash::SessionActivationObserver* observer) {}
+
+void TestSessionController::AddObserver(ash::SessionObserver* observer) {}
+
+void TestSessionController::RemoveObserver(ash::SessionObserver* observer) {}

chrome/browser/ui/ash/test_session_controller.h

@@ -70,6 +70,8 @@ class TestSessionController : public ash::SessionController {
   void RemoveSessionActivationObserverForAccountId(
       const AccountId& account_id,
       ash::SessionActivationObserver* observer) override;
+  void AddObserver(ash::SessionObserver* observer) override;
+  void RemoveObserver(ash::SessionObserver* observer) override;
 
  private:
   base::Optional<ash::SessionInfo> last_session_info_;