Simplify Supplementables post Oilpan.

third_party/WebKit/Source/core/clipboard/DataObject.cpp

 /*
  * Copyright (c) 2008, 2009, 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 241 matching lines @@
 
 void DataObject::internalAddFileItem(DataObjectItem* item)
 {
     ASSERT(item->kind() == DataObjectItem::FileKind);
     m_itemList.append(item);
 }
 
 DEFINE_TRACE(DataObject)
 {
     visitor->trace(m_itemList);
-    HeapSupplementable<DataObject>::trace(visitor);
+    Supplementable<DataObject>::trace(visitor);
 }
 
 DataObject* DataObject::create(WebDragData data)
 {
     DataObject* dataObject = create();
 
     WebVector<WebDragData::Item> items = data.items();
     for (unsigned i = 0; i < items.size(); ++i) {
         WebDragData::Item item = items[i];
 
@@ skipping 74 matching lines @@
         }
         item.title = originalItem->title();
         item.baseURL = originalItem->baseURL();
         itemList[i] = item;
     }
     data.swapItems(itemList);
     return data;
 }
 
 } // namespace blink