Get rid of AXComputedObjectAttributeCache

Source/core/accessibility/AXObject.h

 /*
  * Copyright (C) 2008, 2009, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nuanti Ltd.
  *
  * 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.
@@ skipping 561 matching lines @@
     // If this object itself scrolls, return its ScrollableArea.
     virtual ScrollableArea* getScrollableAreaIfScrollable() const { return 0; }
     virtual void scrollTo(const IntPoint&) const { }
 
     AccessibilityRole buttonRoleType() const;
 
     bool allowsTextRanges() const { return isTextControl(); }
     unsigned getLengthForTextRange() const { return text().length(); }
 
     bool m_detached;
+
+private:
+    // The following cached attribute values are only valid if m_lastModificationCount matches AXObjectCacheImpl::modificationCount().

[aboxhall, 2014/10/23 21:48:11]

What does "the following cached attribute values" here refer to?

Oh right, just m_cachedIsIgnored. Perhaps this could be reworded slightly more
clearly, something like
"The cached attribute values starting with m_cached* are only valid if
m_lastModificationCount matches ..."

[dmazzoni, 2014/10/23 21:51:52]

Sure. In the following changes I'm hoping to add several more.

+    mutable int m_lastModificationCount;
+    mutable bool m_cachedIsIgnored;
+
+    void updateCachedAttributeValuesIfNeeded() const;
 };
 
 #define DEFINE_AX_OBJECT_TYPE_CASTS(thisType, predicate) \
     DEFINE_TYPE_CASTS(thisType, AXObject, object, object->predicate, object.predicate)
 
 } // namespace blink
 
 #endif // AXObject_h