Add support to generate shutdown confirmation dialog

Shutdown confirmation dialog is used to display/highlight specific
information to the user prior to shutdown/restart eg. like a slow
reboot following an OS update or similar use-cases. The shutdown
confirmation dialog allows customized dialog title and message depending
on the use-case.

Bug: b/129056373
Change-Id: Ibaa9473e979314acf4856f6ac646cda209d0e303
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2001723
Commit-Queue: Karthikeyan Ramasubramanian <kramasub@chromium.org>
Reviewed-by: James Cook <jamescook@chromium.org>
Cr-Commit-Position: refs/heads/master@{#736542}

ash/BUILD.gn

@@ -939,6 +939,8 @@ component("ash") {
     "system/session/logout_confirmation_dialog.h",
     "system/session/session_limit_notification_controller.cc",
     "system/session/session_limit_notification_controller.h",
+    "system/session/shutdown_confirmation_dialog.cc",
+    "system/session/shutdown_confirmation_dialog.h",
     "system/status_area_layout_manager.cc",
     "system/status_area_layout_manager.h",
     "system/status_area_widget.cc",

ash/ash_strings.grd

@@ -1575,6 +1575,12 @@ This file contains the strings for ash.
       <message name="IDS_ASH_YES_BUTTON" desc="The text for the button on a dialog OK button that agrees to the contents of the dialog.">
         Yes
       </message>
+      <message name="IDS_ASH_SHUTDOWN_CONFIRMATION_OK_BUTTON" desc="The text for the OK button in the shutdown confirmation dialog.">
+        Restart
+      </message>
+      <message name="IDS_ASH_SHUTDOWN_CONFIRMATION_CANCEL_BUTTON" desc="The text for the Cancel button in the shutdown confirmation dialog.">
+        Do it later
+      </message>
 
       <message name="IDS_ASH_AUTO_NIGHT_LIGHT_NOTIFY_TITLE" desc="The title of the notification shown when Night Light turns on automatically when the auto-night-light feature is enabled.">
         Night Light turns on automatically at sunset

ash/system/session/shutdown_confirmation_dialog.cc

+// Copyright 2020 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/system/session/shutdown_confirmation_dialog.h"
+
+#include <memory>
+#include <utility>
+
+#include "ash/public/cpp/shell_window_ids.h"
+#include "ash/shell.h"
+#include "ash/strings/grit/ash_strings.h"
+#include "base/bind.h"
+#include "ui/base/l10n/l10n_util.h"
+#include "ui/base/ui_base_types.h"
+#include "ui/views/border.h"
+#include "ui/views/controls/label.h"
+#include "ui/views/layout/fill_layout.h"
+#include "ui/views/layout/layout_provider.h"
+#include "ui/views/widget/widget.h"
+
+namespace ash {
+
+namespace {
+
+// Default width of the dialog in DIPs.
+constexpr int kDefaultWidth = 448;
+
+}  // namespace
+
+ShutdownConfirmationDialog::ShutdownConfirmationDialog(
+    int window_title_text_id,
+    int dialog_text_id,
+    base::OnceClosure on_accept_callback,
+    base::OnceClosure on_cancel_callback)
+    : window_title_(l10n_util::GetStringUTF16(window_title_text_id)),
+      on_accept_callback_(std::move(on_accept_callback)),
+      on_cancel_callback_(std::move(on_cancel_callback)) {
+  DialogDelegate::set_button_label(
+      ui::DIALOG_BUTTON_OK,
+      l10n_util::GetStringUTF16(IDS_ASH_SHUTDOWN_CONFIRMATION_OK_BUTTON));
+  DialogDelegate::set_button_label(
+      ui::DIALOG_BUTTON_CANCEL,
+      l10n_util::GetStringUTF16(IDS_ASH_SHUTDOWN_CONFIRMATION_CANCEL_BUTTON));
+  SetLayoutManager(std::make_unique<views::FillLayout>());
+  SetBorder(views::CreateEmptyBorder(
+      views::LayoutProvider::Get()->GetDialogInsetsForContentType(
+          views::TEXT, views::TEXT)));
+
+  label_ = new views::Label;
+  label_->SetHorizontalAlignment(gfx::ALIGN_LEFT);
+  label_->SetMultiLine(true);
+  label_->SetText(l10n_util::GetStringUTF16(dialog_text_id));
+  AddChildView(label_);
+
+  // Parent the dialog widget to the PowerButtonAnimationContainer
+  int container_id = kShellWindowId_PowerButtonAnimationContainer;
+  views::Widget* widget = CreateDialogWidget(
+      this, nullptr,
+      Shell::GetContainer(ash::Shell::GetRootWindowForNewWindows(),
+                          container_id));
+  widget->Show();
+}
+
+ShutdownConfirmationDialog::~ShutdownConfirmationDialog() = default;
+
+bool ShutdownConfirmationDialog::Accept() {
+  std::move(on_accept_callback_).Run();
+  return true;
+}
+
+bool ShutdownConfirmationDialog::Cancel() {
+  std::move(on_cancel_callback_).Run();
+  return true;
+}
+
+ui::ModalType ShutdownConfirmationDialog::GetModalType() const {
+  return ui::MODAL_TYPE_SYSTEM;
+}
+
+base::string16 ShutdownConfirmationDialog::GetWindowTitle() const {
+  return window_title_;
+}
+
+bool ShutdownConfirmationDialog::ShouldShowCloseButton() const {
+  return false;
+}
+
+gfx::Size ShutdownConfirmationDialog::CalculatePreferredSize() const {
+  return gfx::Size(
+      kDefaultWidth,
+      GetLayoutManager()->GetPreferredHeightForWidth(this, kDefaultWidth));
+}
+
+}  // namespace ash

ash/system/session/shutdown_confirmation_dialog.h

+// Copyright 2020 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_SYSTEM_SESSION_SHUTDOWN_CONFIRMATION_DIALOG_H_
+#define ASH_SYSTEM_SESSION_SHUTDOWN_CONFIRMATION_DIALOG_H_
+
+#include "base/callback.h"
+#include "base/macros.h"
+#include "base/strings/string16.h"
+#include "ui/views/window/dialog_delegate.h"
+
+namespace views {
+class Label;
+}
+
+namespace ash {
+
+// Defines a dialog for shutdown that require confirmation from users -
+// more specifically for the situation where the subsequent boot is slow.
+class ShutdownConfirmationDialog : public views::DialogDelegateView {
+ public:
+  ShutdownConfirmationDialog(int window_title_text_id,
+                             int dialog_text_id,
+                             base::OnceClosure on_accept_callback,
+                             base::OnceClosure on_cancel_callback);
+  ~ShutdownConfirmationDialog() override;
+
+  // views::DialogDelegateView:
+  bool Accept() override;
+  bool Cancel() override;
+
+  // views::WidgetDelegate:
+  ui::ModalType GetModalType() const override;
+  base::string16 GetWindowTitle() const override;
+  bool ShouldShowCloseButton() const override;
+
+  // views::View:
+  gfx::Size CalculatePreferredSize() const override;
+
+ private:
+  const base::string16 window_title_;
+  base::OnceClosure on_accept_callback_;
+  base::OnceClosure on_cancel_callback_;
+  views::Label* label_;
+
+  DISALLOW_COPY_AND_ASSIGN(ShutdownConfirmationDialog);
+};
+
+}  // namespace ash
+
+#endif  // ASH_SYSTEM_SESSION_SHUTDOWN_CONFIRMATION_DIALOG_H_