Oilpan: Switch RefCountedGarbageCollected to GarbageCollectedFinalized for Node.

public/platform/WebPrivatePtr.h

Index: public/platform/WebPrivatePtr.h
diff --git a/public/platform/WebPrivatePtr.h b/public/platform/WebPrivatePtr.h
index 6af8bfc7a1c6318de62e4d33425a3179fb848fe9..b7ff90513a2844f3159d1b137e50a09a771b9ac1 100644
--- a/public/platform/WebPrivatePtr.h
+++ b/public/platform/WebPrivatePtr.h
@@ -114,6 +114,7 @@ public:
     }
 
     void assign(T* ptr) { assign(RawPtr<T>(ptr)); }
+    template<typename U> void assign(const RawPtr<U>& val) { assign(RawPtr<T>(val)); }
 
     void assign(const PtrStorageImpl& other) { assign(other.get()); }