[Multipaste] Restore the a11y focus ring after closing the menu

This CL notifies the accessibility side of the closed multipaste menu.
It helps to update the a11y focus ring's location and generate the
suitable voice announcement.

Bug: 1146473
Change-Id: I3892286f6187a9206426af89c1e442cf78362af4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2523058
Commit-Queue: Andrew Xu <andrewxu@chromium.org>
Reviewed-by: Alex Newcomer <newcomer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#825162}

ash/clipboard/clipboard_history_menu_model_adapter.cc

@@ -8,7 +8,9 @@
 #include "ash/clipboard/clipboard_history_util.h"
 #include "ash/clipboard/views/clipboard_history_item_view.h"
 #include "ash/public/cpp/clipboard_image_model_factory.h"
+#include "ash/wm/window_util.h"
 #include "base/metrics/histogram_macros.h"
+#include "ui/accessibility/ax_enums.mojom.h"
 #include "ui/base/clipboard/clipboard.h"
 #include "ui/base/data_transfer_policy/data_transfer_endpoint.h"
 #include "ui/base/data_transfer_policy/data_transfer_policy_controller.h"
@@ -21,6 +23,7 @@
 #include "ui/views/controls/menu/menu_runner.h"
 #include "ui/views/controls/menu/menu_types.h"
 #include "ui/views/controls/menu/submenu_view.h"
+#include "ui/views/widget/widget.h"
 
 namespace ash {
 
@@ -351,6 +354,21 @@ void ClipboardHistoryMenuModelAdapter::OnMenuClosed(views::MenuItemView* menu) {
                       user_journey_time);
   views::MenuModelAdapter::OnMenuClosed(menu);
   item_views_by_command_id_.clear();
+
+  // This implementation of MenuModelAdapter does not have a widget so we need
+  // to manually notify the accessibility side of the closed menu.
+  aura::Window* active_window = window_util::GetActiveWindow();
+  if (!active_window)
+    return;
+  views::Widget* active_widget =
+      views::Widget::GetWidgetForNativeView(active_window);
+  DCHECK(active_widget);
+  views::View* focused_view =
+      active_widget->GetFocusManager()->GetFocusedView();
+  if (focused_view) {
+    focused_view->NotifyAccessibilityEvent(ax::mojom::Event::kMenuEnd,
+                                           /*send_native_event=*/true);
+  }
 }
 
 }  // namespace ash