Oilpan: Make the Node hierarchy RefCountedGarbageCollected instead of TreeShared.

Source/wtf/PassRefPtr.h

Index: Source/wtf/PassRefPtr.h
diff --git a/Source/wtf/PassRefPtr.h b/Source/wtf/PassRefPtr.h
index 828a5ef9cafc4fab8c8fa51550539ded5345f652..1d21a538bf53329ca589d9de5783c4c86d614c51 100644
--- a/Source/wtf/PassRefPtr.h
+++ b/Source/wtf/PassRefPtr.h
@@ -138,6 +138,16 @@ namespace WTF {
         return a == b.get();
     }
 
+    template<typename T, typename U> inline bool operator==(const PassRefPtr<T>& a, const RawPtr<U>& b)
+    {
+        return a.get() == b.get();
+    }
+
+    template<typename T, typename U> inline bool operator==(const RawPtr<T>& a, const PassRefPtr<U>& b)
+    {
+        return a.get() == b.get();
+    }
+
     template<typename T, typename U> inline bool operator!=(const PassRefPtr<T>& a, const PassRefPtr<U>& b)
     {
         return a.get() != b.get();
@@ -163,6 +173,16 @@ namespace WTF {
         return a != b.get();
     }
 
+    template<typename T, typename U> inline bool operator!=(const PassRefPtr<T>& a, const RawPtr<U>& b)
+    {
+        return a.get() != b.get();
+    }
+
+    template<typename T, typename U> inline bool operator!=(const RawPtr<T>& a, const PassRefPtr<U>& b)
+    {
+        return a.get() != b.get();
+    }
+
     template<typename T> inline PassRefPtr<T> adoptRef(T* p)
     {
         adopted(p);