Ignores ARIA relations (e.g. aria-labelledby) that point to an invisible target.

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

 /*
  * Copyright (C) 2012, 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 553 matching lines @@
         role = buttonRoleType();
 
     role = remapAriaRoleDueToParent(role);
 
     if (role)
         return role;
 
     return UnknownRole;
 }
 
-void AXNodeObject::accessibilityChildrenFromAttribute(QualifiedName attr, AXObject::AXObjectVector& children) const
+void AXNodeObject::accessibilityChildrenFromAttribute(QualifiedName attr, AXObject::AXObjectVector& children, bool includeHiddenObjects) const
 {
     HeapVector<Member<Element>> elements;
     elementsFromAttribute(elements, attr);
 
     AXObjectCacheImpl& cache = axObjectCache();
     for (const auto& element : elements) {
-        if (AXObject* child = cache.getOrCreate(element))
+        if (AXObject* child = cache.getOrCreate(element)) {
+            if (!includeHiddenObjects && child->isHiddenForTextAlternativeCalculation())

[aboxhall, 2016/07/08 17:12:35]

Why not just call child->accessibilityIsIgnored() here?

+                continue;
             children.append(child);
+        }
     }
 }
 
 // This only returns true if this is the element that actually has the
 // contentEditable attribute set, unlike node->hasEditableStyle() which will
 // also return true if an ancestor is editable.
 bool AXNodeObject::hasContentEditableAttributeSet() const
 {
     const AtomicString& contentEditableValue = getAttribute(contenteditableAttr);
     if (contentEditableValue.isNull())
@@ skipping 2240 matching lines @@
     return placeholder;
 }
 
 DEFINE_TRACE(AXNodeObject)
 {
     visitor->trace(m_node);
     AXObject::trace(visitor);
 }
 
 } // namespace blink