Get rid of postToElement argument for accessibility notifications.

Source/modules/accessibility/AXObjectCacheImpl.h

Index: Source/modules/accessibility/AXObjectCacheImpl.h
diff --git a/Source/modules/accessibility/AXObjectCacheImpl.h b/Source/modules/accessibility/AXObjectCacheImpl.h
index f71f6529fbe45292fb2677eb60854958bcf7cd52..09caa2a78105e46bbffabd84b3de64134124a5b3 100644
--- a/Source/modules/accessibility/AXObjectCacheImpl.h
+++ b/Source/modules/accessibility/AXObjectCacheImpl.h
@@ -153,9 +153,9 @@ public:
     // as long as the modification count hasn't changed.
     int modificationCount() const { return m_modificationCount; }
 
-    void postNotification(LayoutObject*, AXNotification, bool postToElement);
-    void postNotification(Node*, AXNotification, bool postToElement);
-    void postNotification(AXObject*, AXNotification, bool postToElement);
+    void postNotification(LayoutObject*, AXNotification);
+    void postNotification(Node*, AXNotification);
+    void postNotification(AXObject*, AXNotification);
 
 protected:
     void postPlatformNotification(AXObject*, AXNotification);