Call CXFA_Object::ToNode() rather than C-style casting.

xfa/src/fxfa/src/parser/xfa_script_nodehelper.cpp

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "xfa/src/foxitlib.h"
 #include "xfa/src/fxfa/src/common/xfa_utils.h"
 #include "xfa/src/fxfa/src/common/xfa_object.h"
 #include "xfa/src/fxfa/src/common/xfa_document.h"
@@ skipping 335 matching lines @@
     CFX_WideString wsCondition,
     FX_BOOL bLastNode,
     CXFA_ScriptContext* pScriptContext) {
   if (m_pCreateParent == NULL) {
     return FALSE;
   }
   FX_BOOL bIsClassName = FALSE;
   FX_BOOL bResult = FALSE;
   if (wsName.GetAt(0) == '!') {
     wsName = wsName.Right(wsName.GetLength() - 1);
-    m_pCreateParent = (CXFA_Node*)pScriptContext->GetDocument()->GetXFAObject(
-        XFA_HASHCODE_Datasets);
+    m_pCreateParent = ToNode(
+        pScriptContext->GetDocument()->GetXFAObject(XFA_HASHCODE_Datasets));
   }
   if (wsName.GetAt(0) == '#') {
     bIsClassName = TRUE;
     wsName = wsName.Right(wsName.GetLength() - 1);
   }
   if (m_iCreateCount == 0) {
     XFA_CreateNode_ForCondition(wsCondition);
   }
   if (bIsClassName) {
     XFA_LPCELEMENTINFO lpElement = XFA_GetElementByName(wsName);
@@ skipping 54 matching lines @@
       XFA_ResolveNodes_GetParent(refNode, XFA_LOGIC_NoTransparent);
   if (parent != NULL && refNode != NULL) {
     XFA_LPCPROPERTY pPropert = XFA_GetPropertyOfElement(
         parent->GetClassID(), refNode->GetClassID(), XFA_XDPPACKET_UNKNOWN);
     if (pPropert) {
       bRes = TRUE;
     }
   }
   return bRes;
 }