Implement new approach for debugging leaked wrapper object references (issue #2593)

libcef_dll/cpptoc/client_cpptoc.h

@@ -9,7 +9,7 @@
 // implementations. See the translator.README.txt file in the tools directory
 // for more information.
 //
-// $hash=9ac6fdead48b09acbc98b6f6fd3bbb8e194afb96$
+// $hash=5d4c102c7afa917066d0a76cb41f758e86571b71$
 //
 
 #ifndef CEF_LIBCEF_DLL_CPPTOC_CLIENT_CPPTOC_H_
@@ -30,6 +30,7 @@ class CefClientCppToC
     : public CefCppToCRefCounted<CefClientCppToC, CefClient, cef_client_t> {
  public:
   CefClientCppToC();
+  virtual ~CefClientCppToC();
 };
 
 #endif  // CEF_LIBCEF_DLL_CPPTOC_CLIENT_CPPTOC_H_