Remove more oilpan.

sky/engine/core/dom/Document.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
@@ skipping 127 matching lines @@
 enum DocumentClass {
     DefaultDocumentClass = 0,
     HTMLDocumentClass = 1,
     MediaDocumentClass = 1 << 4,
 };
 
 typedef unsigned char DocumentClassFlags;
 
 class Document;
 
-class DocumentVisibilityObserver : public DummyBase<void> {
+class DocumentVisibilityObserver {
 public:
     DocumentVisibilityObserver(Document&);
     virtual ~DocumentVisibilityObserver();
 
     virtual void didChangeVisibilityState(PageVisibilityState) = 0;
 
     // Classes that inherit Node and DocumentVisibilityObserver must have a
     // virtual override of Node::didMoveToNewDocument that calls
     // DocumentVisibilityObserver::setDocument
     void setObservedDocument(Document&);
 
 private:
     void registerObserver(Document&);
     void unregisterObserver();
 
     RawPtr<Document> m_document;
 };
 
 class Document : public ContainerNode, public TreeScope, public ExecutionContext, public ExecutionContextClient
     , public DocumentSupplementable, public LifecycleContext<Document>, public ResourceClient {
     DEFINE_WRAPPERTYPEINFO();
-    WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(Document);
 public:
     static PassRefPtr<Document> create(const DocumentInit& initializer = DocumentInit())
     {
         return adoptRef(new Document(initializer));
     }
     virtual ~Document();
 
     // Called by JS.
     static PassRefPtr<Document> create(Document&);
 
@@ skipping 689 matching lines @@
 Node* eventTargetNodeForDocument(Document*);
 
 } // namespace blink
 
 #ifndef NDEBUG
 // Outside the WebCore namespace for ease of invocation from gdb.
 void showLiveDocumentInstances();
 #endif
 
 #endif // Document_h