Revert of Don't keep recreating AXMenuListPopup

Source/modules/accessibility/AXMenuList.cpp

Index: Source/modules/accessibility/AXMenuList.cpp
diff --git a/Source/modules/accessibility/AXMenuList.cpp b/Source/modules/accessibility/AXMenuList.cpp
index f21b0f6f5b083b96af8c27e1257e7432f9a90ec6..6e7b9029e772a95f4086403772897897586fbb47 100644
--- a/Source/modules/accessibility/AXMenuList.cpp
+++ b/Source/modules/accessibility/AXMenuList.cpp
@@ -93,6 +93,15 @@
     list->addChildren();
 }
 
+void AXMenuList::childrenChanged()
+{
+    if (m_children.isEmpty())
+        return;
+
+    ASSERT(m_children.size() == 1);
+    m_children[0]->childrenChanged();
+}
+
 bool AXMenuList::isCollapsed() const
 {
     return !toLayoutMenuList(m_layoutObject)->popupIsVisible();