[M60 Merge] No AX objects for comments and other irrelevant node types

third_party/WebKit/Source/modules/accessibility/AXObjectCacheImpl.cpp

 /*
  * Copyright (C) 2014, Google 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
@@ skipping 332 matching lines @@
 
 AXObjectImpl* AXObjectCacheImpl::CreateFromInlineTextBox(
     AbstractInlineTextBox* inline_text_box) {
   return AXInlineTextBox::Create(inline_text_box, *this);
 }
 
 AXObjectImpl* AXObjectCacheImpl::GetOrCreate(Node* node) {
   if (!node)
     return 0;
 
+  if (!node->IsElementNode() && !node->IsTextNode() && !node->IsDocumentNode())
+    return 0;  // Only documents, elements and text nodes get a11y objects
+
   if (AXObjectImpl* obj = Get(node))
     return obj;
 
   // If the node has a layout object, prefer using that as the primary key for
   // the AXObjectImpl, with the exception of an HTMLAreaElement, which is
   // created based on its node.
   if (node->GetLayoutObject() && !isHTMLAreaElement(node))
     return GetOrCreate(node->GetLayoutObject());
 
   if (!node->parentElement())
@@ skipping 897 matching lines @@
   visitor->Trace(document_);
   visitor->Trace(node_object_mapping_);
 
   visitor->Trace(objects_);
   visitor->Trace(notifications_to_post_);
 
   AXObjectCache::Trace(visitor);
 }
 
 }  // namespace blink