Only call TextChanged on existing AXObjects. This avoids triggering the code which calls UpdateDist…

third_party/WebKit/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 99 matching lines @@
 }
 
 bool AXMenuList::CanSetFocusAttribute() const {
   if (!GetNode())
     return false;
 
   return !ToElement(GetNode())->IsDisabledFormControl();
 }
 
 void AXMenuList::DidUpdateActiveOption(int option_index) {
+  bool suppress_notifications =
+      (GetNode() && !GetNode()->IsFinishedParsingChildren());
   const auto& child_objects = Children();
   if (!child_objects.IsEmpty()) {
     DCHECK(child_objects.size() == 1);
     DCHECK(child_objects[0]->IsMenuListPopup());
 
     if (child_objects[0]->IsMenuListPopup()) {
       if (AXMenuListPopup* popup = ToAXMenuListPopup(child_objects[0].Get()))
-        popup->DidUpdateActiveOption(option_index);
+        popup->DidUpdateActiveOption(option_index, !suppress_notifications);
     }
   }
 
   AxObjectCache().PostNotification(this,
                                    AXObjectCacheImpl::kAXMenuListValueChanged);
 }
 
 void AXMenuList::DidShowPopup() {
   if (Children().size() != 1)
     return;
 
   AXMenuListPopup* popup = ToAXMenuListPopup(Children()[0].Get());
   popup->DidShow();
 }
 
 void AXMenuList::DidHidePopup() {
   if (Children().size() != 1)
     return;
 
   AXMenuListPopup* popup = ToAXMenuListPopup(Children()[0].Get());
   popup->DidHide();
 
   if (GetNode() && GetNode()->IsFocused())
     AxObjectCache().PostNotification(
         this, AXObjectCacheImpl::kAXFocusedUIElementChanged);
 }
 
 }  // namespace blink