Replace calls to deprecated CFX_{Wide,Byte}String::Empty()

xfa/fxfa/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/fxfa/parser/xfa_script_nodehelper.h"
 
 #include "core/fxcrt/include/fx_ext.h"
 #include "xfa/fxfa/fm2js/xfa_fm2jsapi.h"
@@ skipping 243 matching lines @@
     if (child == pNode) {
       return i;
     }
   }
   return 0;
 }
 void CXFA_NodeHelper::XFA_GetNameExpression(CXFA_Node* refNode,
                                             CFX_WideString& wsName,
                                             FX_BOOL bIsAllPath,
                                             XFA_LOGIC_TYPE eLogicType) {
-  wsName.Empty();
+  wsName.clear();
   if (bIsAllPath) {
     XFA_GetNameExpression(refNode, wsName, FALSE, eLogicType);
     CFX_WideString wsParent;
     CXFA_Node* parent =
         XFA_ResolveNodes_GetParent(refNode, XFA_LOGIC_NoTransparent);
     while (parent) {
       XFA_GetNameExpression(parent, wsParent, FALSE, eLogicType);
       wsParent += L".";
       wsParent += wsName;
       wsName = wsParent;
@@ skipping 145 matching lines @@
     m_eLastCreateType = XFA_ELEMENT_DataValue;
   }
 }
 FX_BOOL CXFA_NodeHelper::XFA_NodeIsProperty(CXFA_Node* refNode) {
   CXFA_Node* parent =
       XFA_ResolveNodes_GetParent(refNode, XFA_LOGIC_NoTransparent);
   return parent && refNode &&
          XFA_GetPropertyOfElement(parent->GetClassID(), refNode->GetClassID(),
                                   XFA_XDPPACKET_UNKNOWN);
 }