Get rid of AXComputedObjectAttributeCache

Source/core/accessibility/AXObject.cpp

 /*
  * Copyright (C) 2008, 2009, 2011 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
@@ skipping 116 matching lines @@
         roleMap->set(roles[i].ariaRole, roles[i].webcoreRole);
     return roleMap;
 }
 
 AXObject::AXObject()
     : m_id(0)
     , m_haveChildren(false)
     , m_role(UnknownRole)
     , m_lastKnownIsIgnoredValue(DefaultBehavior)
     , m_detached(false)
+    , m_lastModificationCount(-1)
+    , m_cachedIsIgnored(false)
 {
 }
 
 AXObject::~AXObject()
 {
     ASSERT(isDetached());
 }
 
 void AXObject::detach()
 {
@@ skipping 94 matching lines @@
     case TextFieldRole:
     case ToggleButtonRole:
         return true;
     default:
         return false;
     }
 }
 
 bool AXObject::accessibilityIsIgnored() const
 {
+    updateCachedAttributeValuesIfNeeded();
+    return m_cachedIsIgnored;
+}
+
+void AXObject::updateCachedAttributeValuesIfNeeded() const
+{
     AXObjectCacheImpl* cache = axObjectCache();
     if (!cache)
-        return true;
+        return;
 
-    AXComputedObjectAttributeCache* attributeCache = cache->computedObjectAttributeCache();
-    if (attributeCache) {
-        AXObjectInclusion ignored = attributeCache->getIgnored(axObjectID());
-        switch (ignored) {
-        case IgnoreObject:
-            return true;
-        case IncludeObject:
-            return false;
-        case DefaultBehavior:
-            break;
-        }
-    }
+    if (cache->modificationCount() == m_lastModificationCount)
+        return;
 
-    bool result = computeAccessibilityIsIgnored();
-
-    if (attributeCache)
-        attributeCache->setIgnored(axObjectID(), result ? IgnoreObject : IncludeObject);
-
-    return result;
+    m_cachedIsIgnored = computeAccessibilityIsIgnored();
+    m_lastModificationCount = cache->modificationCount();
 }
 
 bool AXObject::accessibilityIsIgnoredByDefault() const
 {
     return defaultObjectInclusion() == IgnoreObject;
 }
 
 AXObjectInclusion AXObject::accessibilityPlatformIncludesObject() const
 {
     if (isMenuListPopup() || isMenuListOption())
@@ skipping 632 matching lines @@
         return ToggleButtonRole;
     if (ariaHasPopup())
         return PopUpButtonRole;
     // We don't contemplate RadioButtonRole, as it depends on the input
     // type.
 
     return ButtonRole;
 }
 
 } // namespace blink