Move CSSCalcExpressionNode and subclasses to the oilpan heap.

Source/wtf/RawPtr.h

 /*
  * Copyright (C) 2014 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 27 matching lines @@
 // use reference counting or garbage collection based on a
 // compile-time flag.
 
 namespace WTF {
 
 template<typename T>
 class RawPtr {
 public:
     RawPtr() : m_ptr(0) { }
     RawPtr(T* ptr) : m_ptr(ptr) { }
-
-    template<typename U>
-    explicit RawPtr(const RawPtr<U>& other)
+    RawPtr(const RawPtr& other)
         : m_ptr(other.get())
     {
     }
+    template<typename U>
+    RawPtr(const RawPtr<U>& other)
+        : m_ptr(other.get())
+    {
+    }
 
     T* get() const { return m_ptr; }
     void clear() { m_ptr = 0; }
     // FIXME: oilpan: Remove release and leakRef once we remove RefPtrWillBeRawPtr.
     RawPtr<T> release()
     {
         RawPtr<T> tmp = m_ptr;
         m_ptr = 0;
         return tmp;
     }
     T* leakRef()
     {
         T* ptr = m_ptr;
         m_ptr = 0;
         return ptr;
     }
 
-    RawPtr& operator=(T* ptr)
+    template<typename U>
+    RawPtr& operator=(U* ptr)
     {
         m_ptr = ptr;
         return *this;
     }
 
+    template<typename U>
+    RawPtr& operator=(RawPtr<U> ptr)
+    {
+        m_ptr = ptr.get();
+        return *this;
+    }
+
     operator T*() const { return m_ptr; }
     T& operator*() const { return *m_ptr; }
     T* operator->() const { return m_ptr; }
 
 private:
     T* m_ptr;
 };
 
 } // namespace WTF
 
 using WTF::RawPtr;
 
 #endif