[Merge to XFA] Revert "Revert "Add type cast definitions for CPDF_Dictionary.""

fpdfsdk/src/fsdk_baseform.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 "../../third_party/base/nonstd_unique_ptr.h"
 #include "../include/fsdk_define.h"
 #include "../include/fpdfxfa/fpdfxfa_doc.h"
 #include "../include/fpdfxfa/fpdfxfa_util.h"
@@ skipping 520 matching lines @@
   int nFieldType = GetFieldType();
   switch (nFieldType) {
     case FIELDTYPE_PUSHBUTTON:
     case FIELDTYPE_COMBOBOX:
     case FIELDTYPE_LISTBOX:
     case FIELDTYPE_TEXTFIELD:
     case FIELDTYPE_SIGNATURE:
       return psub->GetType() == PDFOBJ_STREAM;
     case FIELDTYPE_CHECKBOX:
     case FIELDTYPE_RADIOBUTTON:
-      if (psub->GetType() == PDFOBJ_DICTIONARY) {
-        CPDF_Dictionary* pSubDict = (CPDF_Dictionary*)psub;
+      if (CPDF_Dictionary* pSubDict = psub->AsDictionary()) {
         return pSubDict->GetStream(GetAppState()) != NULL;
       }
       return FALSE;
   }
   return TRUE;
 }
 
 int CPDFSDK_Widget::GetFieldType() const {
   CPDF_FormField* pField = GetFormField();
   ASSERT(pField != NULL);
@@ skipping 2802 matching lines @@
   ASSERT(pAnnot != NULL);
 
   CPDF_Annot* pPDFAnnot = pAnnot->GetPDFAnnot();
   ASSERT(pPDFAnnot != NULL);
 
   CPDF_Rect rcAnnot;
   pPDFAnnot->GetRect(rcAnnot);
 
   return rcAnnot;
 }