Oilpan: make DataObject and SharedWorker heap Supplementables.

Source/modules/filesystem/DraggedIsolatedFileSystem.cpp

 /*
  * Copyright (C) 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 40 matching lines @@
     return m_filesystem.get();
 }
 
 // static
 const char* DraggedIsolatedFileSystem::supplementName()
 {
     ASSERT(isMainThread());
     return "DraggedIsolatedFileSystem";
 }
 
+DraggedIsolatedFileSystem* DraggedIsolatedFileSystem::from(DataObject* dataObject)
+{
+    return static_cast<DraggedIsolatedFileSystem*>(WillBeHeapSupplement<DataObject>::from(dataObject, supplementName()));
+}
+
 DraggedIsolatedFileSystem::DraggedIsolatedFileSystem(const String& filesystemId)
     : m_filesystemId(filesystemId)
 {
 }
 
+void DraggedIsolatedFileSystem::trace(Visitor* visitor)
+{
+    visitor->trace(m_filesystem);
+}
+
 } // namespace WebCore