Make down-conversion explicit from CFX_Widetring to CFX_WideStringC.

xfa/fxfa/app/xfa_ffpageview.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/include/fxfa/xfa_ffpageview.h"
 
 #include "xfa/fde/fde_render.h"
 #include "xfa/fxfa/app/xfa_ffcheckbutton.h"
@@ skipping 252 matching lines @@
 }
 CXFA_FFWidget* CXFA_FFTabOrderPageWidgetIterator::GetTraverseWidget(
     CXFA_FFWidget* pWidget) {
   CXFA_WidgetAcc* pAcc = pWidget->GetDataAcc();
   CXFA_Node* pTraversal = pAcc->GetNode()->GetChild(0, XFA_ELEMENT_Traversal);
   if (pTraversal) {
     CXFA_Node* pTraverse = pTraversal->GetChild(0, XFA_ELEMENT_Traverse);
     if (pTraverse) {
       CFX_WideString wsTraverseWidgetName;
       if (pTraverse->GetAttribute(XFA_ATTRIBUTE_Ref, wsTraverseWidgetName)) {
-        return FindWidgetByName(wsTraverseWidgetName, pWidget);
+        return FindWidgetByName(wsTraverseWidgetName.AsWideStringC(), pWidget);
       }
     }
   }
   return NULL;
 }
 CXFA_FFWidget* CXFA_FFTabOrderPageWidgetIterator::FindWidgetByName(
     const CFX_WideStringC& wsWidgetName,
     CXFA_FFWidget* pRefWidget) {
   return pRefWidget->GetDocView()->GetWidgetByName(wsWidgetName, pRefWidget);
 }
@@ skipping 129 matching lines @@
     CXFA_LayoutItem* pLayoutItem) {
   if (CXFA_FFWidget* pWidget = XFA_GetWidgetFromLayoutItem(pLayoutItem)) {
     if (!pWidget->IsLoaded() &&
         (pWidget->GetStatus() & XFA_WIDGETSTATUS_Visible)) {
       pWidget->LoadWidget();
     }
     return pWidget;
   }
   return NULL;
 }