Oilpan: Prepare moving AXObject to heap

Source/core/dom/AXObjectCache.h

Index: Source/core/dom/AXObjectCache.h
diff --git a/Source/core/dom/AXObjectCache.h b/Source/core/dom/AXObjectCache.h
index 186005aebd0f8d88e2a4a487dc9e6f5a49241dea..85d94b5462c950354260d70eb77d2859899f58a9 100644
--- a/Source/core/dom/AXObjectCache.h
+++ b/Source/core/dom/AXObjectCache.h
@@ -32,6 +32,7 @@
 typedef unsigned AXID;
 
 namespace blink {
+class AbstractInlineTextBox;
 class AXObject;
 class FrameView;
 class HTMLOptionElement;
@@ -96,6 +97,7 @@ public:
     virtual void remove(LayoutObject*) = 0;
     virtual void remove(Node*) = 0;
     virtual void remove(Widget*) = 0;
+    virtual void remove(AbstractInlineTextBox*) = 0;
 
     virtual const Element* rootAXEditableElement(const Node*) = 0;
 
@@ -119,8 +121,6 @@ public:
 
     virtual void setCanvasObjectBounds(Element*, const LayoutRect&) = 0;
 
-    virtual void clearWeakMembers(Visitor*) = 0;
-
     virtual void inlineTextBoxesUpdated(LayoutObject*) = 0;
 
     // Called when the scroll offset changes.