One AXObjectCache per frame

Source/modules/accessibility/AXLayoutObject.h

Index: Source/modules/accessibility/AXLayoutObject.h
diff --git a/Source/modules/accessibility/AXLayoutObject.h b/Source/modules/accessibility/AXLayoutObject.h
index 59cab9f05d985080e3c887b7af85f4e052e8e81f..5aa058c498479b32531d979b293ad9c6d4680c50 100644
--- a/Source/modules/accessibility/AXLayoutObject.h
+++ b/Source/modules/accessibility/AXLayoutObject.h
@@ -43,7 +43,6 @@ class FrameView;
 class HTMLAreaElement;
 class IntPoint;
 class Node;
-class Widget;
 
 class MODULES_EXPORT AXLayoutObject : public AXNodeObject {
 protected:
@@ -186,7 +185,6 @@ protected:
     Document* document() const override;
     FrameView* documentFrameView() const override;
     Element* anchorElement() const override;
-    Widget* widgetForAttachmentView() const override;
 
     void setValue(const String&) override;
 
@@ -217,7 +215,6 @@ private:
     void addTextFieldChildren();
     void addImageMapChildren();
     void addCanvasChildren();
-    void addAttachmentChildren();
     void addPopupChildren();
     void addRemoteSVGChildren();
     void addInlineTextBoxChildren(bool force);