Simplify and add caching for accessible bounding box calculation.

Source/core/accessibility/AccessibilityObject.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 485 matching lines @@
 
     // Accessibility Text.
     virtual void accessibilityText(Vector<AccessibilityText>&) { };
     virtual String textUnderElement() const { return String(); }
 
     // Accessibility Text - (To be deprecated).
     virtual String accessibilityDescription() const { return String(); }
     virtual String title() const { return String(); }
     virtual String helpText() const { return String(); }
 
-    // Position and size.
-    virtual LayoutRect boundingBoxRect() const { return LayoutRect(); }
-    IntRect pixelSnappedBoundingBoxRect() const { return pixelSnappedIntRect(boundingBoxRect()); }
-    virtual LayoutRect elementRect() const = 0;
-    IntRect pixelSnappedElementRect() const { return pixelSnappedIntRect(elementRect()); }
-    LayoutSize size() const { return elementRect().size(); }
-    IntSize pixelSnappedSize() const { return elementRect().pixelSnappedSize(); }
+    // Location and click point in frame-relative coordinates.
+    virtual LayoutRect elementRect() const { return LayoutRect(); }
+    virtual void checkCachedElementRect() const { }
+    virtual void updateCachedElementRect() const { }
+    virtual void markCachedElementRectDirty() const;
     virtual IntPoint clickPoint();
-    static IntRect boundingBoxForQuads(RenderObject*, const Vector<FloatQuad>&);
 
     // Hit testing.
     // Called on the root AX object to return the deepest available element.
     virtual AccessibilityObject* accessibilityHitTest(const IntPoint&) const { return 0; }
     // Called on the AX object after the render tree determines which is the right AccessibilityRenderObject.
     virtual AccessibilityObject* elementAccessibilityHitTest(const IntPoint&) const;
 
     // High-level accessibility tree access. Other modules should only use these functions.
     const AccessibilityChildrenVector& children();
     virtual AccessibilityObject* parentObject() const = 0;
@@ skipping 142 matching lines @@
     // Fenced components.
     virtual String mathFencedOpenString() const { return String(); }
     virtual String mathFencedCloseString() const { return String(); }
     virtual int mathLineThickness() const { return 0; }
 
     // Static helper functions.
     static bool isARIAControl(AccessibilityRole);
     static bool isARIAInput(AccessibilityRole);
     static AccessibilityObject* anchorElementForNode(Node*);
     static AccessibilityRole ariaRoleToWebCoreRole(const String&);
+    static IntRect boundingBoxForQuads(RenderObject*, const Vector<FloatQuad>&);
 
 protected:
     AXID m_id;
     AccessibilityChildrenVector m_children;
     mutable bool m_haveChildren;
     AccessibilityRole m_role;
     AccessibilityObjectInclusion m_lastKnownIsIgnoredValue;
 
     virtual bool computeAccessibilityIsIgnored() const { return true; }
 
@@ skipping 13 matching lines @@
 #if !HAVE(ACCESSIBILITY)
 inline const AccessibilityObject::AccessibilityChildrenVector& AccessibilityObject::children() { return m_children; }
 inline const String& AccessibilityObject::actionVerb() const { return emptyString(); }
 inline int AccessibilityObject::lineForPosition(const VisiblePosition&) const { return -1; }
 inline void AccessibilityObject::updateBackingStore() { }
 #endif
 
 } // namespace WebCore
 
 #endif // AccessibilityObject_h