Implement computedRole and computedName (behind a flag)

Source/modules/accessibility/AXSpinButton.h

Index: Source/modules/accessibility/AXSpinButton.h
diff --git a/Source/modules/accessibility/AXSpinButton.h b/Source/modules/accessibility/AXSpinButton.h
index 2d79cb91c501b5b74bf7afa8d5a55bb8b9c95300..10dd9f4b26f8ce78ef9179cde1e27b3acf178bae 100644
--- a/Source/modules/accessibility/AXSpinButton.h
+++ b/Source/modules/accessibility/AXSpinButton.h
@@ -32,16 +32,18 @@
 
 namespace blink {
 
+class AXObjectCache;
+
 class AXSpinButton final : public AXMockObject {
 public:
-    static PassRefPtr<AXSpinButton> create();
+    static PassRefPtr<AXSpinButton> create(AXObjectCache*);
     virtual ~AXSpinButton();
 
     void setSpinButtonElement(SpinButtonElement* spinButton) { m_spinButtonElement = spinButton; }
     void step(int amount);
 
 private:
-    AXSpinButton();
+    explicit AXSpinButton(AXObjectCache*);
 
     virtual AccessibilityRole roleValue() const override { return SpinButtonRole; }
     virtual bool isSpinButton() const override { return true; }
@@ -54,14 +56,14 @@ private:
 
 class AXSpinButtonPart final : public AXMockObject {
 public:
-    static PassRefPtr<AXSpinButtonPart> create();
+    static PassRefPtr<AXSpinButtonPart> create(AXObjectCache*);
     virtual ~AXSpinButtonPart() { }
 
     bool isIncrementor() const { return m_isIncrementor; }
     void setIsIncrementor(bool value) { m_isIncrementor = value; }
 
 private:
-    AXSpinButtonPart();
+    AXSpinButtonPart(AXObjectCache*);
     bool m_isIncrementor : 1;
 
     virtual bool press() const override;