Fix crash in CXFA_Node::TryUserData() (speculative)

xfa/fxjse/include/fxjse.h

Index: xfa/fxjse/include/fxjse.h
diff --git a/xfa/fxjse/include/fxjse.h b/xfa/fxjse/include/fxjse.h
index d7c85f54e8c80d334afd47aad776e12701d12684..8f30faac307c7c51b8d7cd2536f5ff6061f5ac64 100644
--- a/xfa/fxjse/include/fxjse.h
+++ b/xfa/fxjse/include/fxjse.h
@@ -14,7 +14,11 @@
 class CFXJSE_Arguments;
 class CFXJSE_Value;
 
-class CFXJSE_HostObject {};  // C++ object which can be wrapped by CFXJSE_value.
+// C++ object which can be wrapped by CFXJSE_value.
+class CFXJSE_HostObject {
+ public:
+  virtual ~CFXJSE_HostObject() {}
+};
 
 typedef void (*FXJSE_FuncCallback)(CFXJSE_Value* pThis,
                                    const CFX_ByteStringC& szFuncName,