Create a VarPrivate interface to contain the scripting helper functions of Var.

ppapi/cpp/dev/scriptable_object_deprecated.h

 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef PPAPI_CPP_SCRIPTABLE_OBJECT_DEPRECATED_H_
 #define PPAPI_CPP_SCRIPTABLE_OBJECT_DEPRECATED_H_
 
 #include <vector>
 
 struct PPP_Class_Deprecated;
 
 namespace pp {
 class Var;
+class VarPrivate;
 }
-using pp::Var;
 
 namespace pp {
 
 namespace deprecated {
 
 // This class allows you to implement objects accessible by JavaScript. Derive
 // from this class and override the virtual functions you support. pp::Var has
 // a constructor that takes a pointer to a ScriptableObject for when you want
 // to convert your custom object to a var.
 //
@@ skipping 44 matching lines @@
                    const std::vector<Var>& args,
                    Var* exception);
 
   // The default implementation sets an exception that the method does not
   // exist.
   virtual Var Construct(const std::vector<Var>& args,
                         Var* exception);
 
  private:
   friend class ::pp::Var;
+  friend class ::pp::VarPrivate;
   static const PPP_Class_Deprecated* GetClass();
 
   // Unimplemented, copy and assigmnent is not allowed.
   ScriptableObject(const ScriptableObject& other);
   ScriptableObject& operator=(const ScriptableObject& other);
 };
 
 }  // namespace deprecated
 
 }  // namespace pp
 
 #endif  // PPAPI_CPP_SCRIPTABLE_OBJECT_DEPRECATED_H_