Oilpan: remove unnecessary MultisamplingChangedObserver unregistration.

third_party/WebKit/Source/core/page/Page.h

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2013 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 175 matching lines @@
     void setIsPainting(bool painting) { m_isPainting = painting; }
     bool isPainting() const { return m_isPainting; }
 #endif
 
     class CORE_EXPORT MultisamplingChangedObserver : public WillBeGarbageCollectedMixin {
     public:
         virtual void multisamplingChanged(bool) = 0;
     };
 
     void addMultisamplingChangedObserver(MultisamplingChangedObserver*);
+#if !ENABLE(OILPAN)
     void removeMultisamplingChangedObserver(MultisamplingChangedObserver*);
+#endif
 
     void didCommitLoad(LocalFrame*);
 
     void acceptLanguagesChanged();
 
     static void networkStateChanged(bool online);
 
     MemoryPurgeController& memoryPurgeController();
 
     void purgeMemory(DeviceKind) override;
@@ skipping 69 matching lines @@
     OwnPtrWillBeMember<FrameHost> m_frameHost;
 
     OwnPtrWillBeMember<MemoryPurgeController> m_memoryPurgeController;
 };
 
 extern template class CORE_EXTERN_TEMPLATE_EXPORT WillBeHeapSupplement<Page>;
 
 } // namespace blink
 
 #endif // Page_h