Update desktop tree when Aura windows are removed.

ui/views/accessibility/ax_window_obj_wrapper.cc

Index: ui/views/accessibility/ax_window_obj_wrapper.cc
diff --git a/ui/views/accessibility/ax_window_obj_wrapper.cc b/ui/views/accessibility/ax_window_obj_wrapper.cc
index 5a3bd3d2e5550df685df8a203f2cc9af7ab47d89..7117443cc5c6203df3d26a73e6392a7a4766f141 100644
--- a/ui/views/accessibility/ax_window_obj_wrapper.cc
+++ b/ui/views/accessibility/ax_window_obj_wrapper.cc
@@ -61,7 +61,19 @@ int32_t AXWindowObjWrapper::GetID() {
 }
 
 void AXWindowObjWrapper::OnWindowDestroyed(aura::Window* window) {
-  AXAuraObjCache::GetInstance()->Remove(window);
+  AXAuraObjCache::GetInstance()->Remove(window, nullptr);
+}
+
+void AXWindowObjWrapper::OnWindowDestroying(aura::Window* window) {
+  Widget* widget = Widget::GetWidgetForNativeView(window);
+  if (widget)
+    AXAuraObjCache::GetInstance()->Remove(widget);
+}
+
+void AXWindowObjWrapper::OnWindowHierarchyChanged(
+    const HierarchyChangeParams& params) {
+  if (params.phase == WindowObserver::HierarchyChangeParams::HIERARCHY_CHANGED)
+    AXAuraObjCache::GetInstance()->Remove(params.target, params.old_parent);
 }
 
 }  // namespace views