Update focus when widget changes visibility.

ui/views/accessibility/ax_widget_obj_wrapper.cc

 // Copyright 2014 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 "ui/views/accessibility/ax_widget_obj_wrapper.h"
 
 #include "base/strings/utf_string_conversions.h"
 #include "ui/accessibility/ax_node_data.h"
 #include "ui/views/accessibility/ax_aura_obj_cache.h"
 #include "ui/views/accessibility/ax_aura_obj_wrapper.h"
@@ skipping 44 matching lines @@
 }
 
 void AXWidgetObjWrapper::OnWidgetDestroying(Widget* widget) {
   AXAuraObjCache::GetInstance()->Remove(widget);
 }
 
 void AXWidgetObjWrapper::OnWidgetClosing(Widget* widget) {
   AXAuraObjCache::GetInstance()->Remove(widget);
 }
 
+void AXWidgetObjWrapper::OnWidgetVisibilityChanged(Widget*, bool) {
+  // If a widget changes visibility it may affect what's focused, in particular
+  // when a widget that contains the focused view gets hidden.
+  AXAuraObjCache::GetInstance()->OnFocusedViewChanged();
+}
+
 void AXWidgetObjWrapper::OnWillRemoveView(Widget* widget, View* view) {
   AXAuraObjCache::GetInstance()->RemoveViewSubtree(view);
 }
 
 }  // namespace views