Implement select listbox using shadow DOM

Source/core/accessibility/AXListBoxOption.h

Index: Source/core/accessibility/AXListBoxOption.h
diff --git a/Source/core/accessibility/AXListBoxOption.h b/Source/core/accessibility/AXListBoxOption.h
index 6ea9ab8af88a5e8ba220602ea13d331541078d77..d1d2902ac16bef42077fe35c5f6974b3604a17fe 100644
--- a/Source/core/accessibility/AXListBoxOption.h
+++ b/Source/core/accessibility/AXListBoxOption.h
@@ -29,7 +29,7 @@
 #ifndef AXListBoxOption_h
 #define AXListBoxOption_h
 
-#include "core/accessibility/AXObject.h"
+#include "core/accessibility/AXRenderObject.h"
 #include "core/html/HTMLElement.h"
 #include "wtf/Forward.h"
 
@@ -40,32 +40,24 @@ class Element;
 class HTMLElement;
 class HTMLSelectElement;
 
-class AXListBoxOption FINAL : public AXObject {
+class AXListBoxOption FINAL : public AXRenderObject {
 
 private:
-    AXListBoxOption();
+    AXListBoxOption(RenderObject*);
 public:
-    static PassRefPtr<AXListBoxOption> create();
+    static PassRefPtr<AXListBoxOption> create(RenderObject*);
     virtual ~AXListBoxOption();
 
-    void setHTMLElement(HTMLElement* element) { m_optionElement = element; }
-
     virtual AccessibilityRole roleValue() const OVERRIDE { return ListBoxOptionRole; }
     virtual bool isSelected() const OVERRIDE;
     virtual bool isEnabled() const OVERRIDE;
     virtual bool isSelectedOptionActive() const OVERRIDE;
-    virtual String stringValue() const OVERRIDE;
-    virtual Element* actionElement() const OVERRIDE;
-    virtual Node* node() const OVERRIDE { return m_optionElement; }
     virtual void setSelected(bool) OVERRIDE;
     virtual bool canSetSelectedAttribute() const OVERRIDE;
-
-    virtual LayoutRect elementRect() const OVERRIDE;
-    virtual AXObject* parentObject() const OVERRIDE;
+    virtual String stringValue() const OVERRIDE;
+    virtual String title() const OVERRIDE { return String(); }
 
 private:
-    HTMLElement* m_optionElement;
-
     virtual bool isListBoxOption() const OVERRIDE { return true; }
     virtual bool canHaveChildren() const OVERRIDE { return false; }
     virtual bool computeAccessibilityIsIgnored() const OVERRIDE;