Re-land: Don't keep recreating AXMenuListPopup

Source/modules/accessibility/AXMenuList.cpp

 /*
  * Copyright (C) 2010 Apple Inc. All Rights Reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 42 matching lines @@
 bool AXMenuList::press() const
 {
     LayoutMenuList* menuList = toLayoutMenuList(m_layoutObject);
     if (menuList->popupIsVisible())
         menuList->hidePopup();
     else
         menuList->showPopup();
     return true;
 }
 
+void AXMenuList::updateChildrenIfNecessary()
+{
+    if (m_children.isEmpty()) {
+        addChildren();
+        return;
+    }
+
+    // There's no reason to update our AXMenuListPopup child. If we get a
+    // call to updateChildrenIfNecessary, it's because the options might have
+    // changed, so call it on our popup.
+    ASSERT(m_children.size() == 1);
+    m_children[0]->updateChildrenIfNecessary();
+}
+
 void AXMenuList::clearChildren()
 {
     if (m_children.isEmpty())
         return;
 
     // There's no reason to clear our AXMenuListPopup child. If we get a
     // call to clearChildren, it's because the options might have changed,
     // so call it on our popup.
     ASSERT(m_children.size() == 1);
     m_children[0]->clearChildren();
@@ skipping 81 matching lines @@
         return;
 
     AXMenuListPopup* popup = toAXMenuListPopup(children()[0].get());
     popup->didHide();
 
     if (node() && node()->focused())
         axObjectCache()->postNotification(this, AXObjectCacheImpl::AXFocusedUIElementChanged);
 }
 
 } // namespace blink