Remove even more const casting from core.

core/fpdfdoc/doc_utils.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 <algorithm>
 #include <vector>
 
 #include "core/fpdfapi/fpdf_font/include/cpdf_font.h"
@@ skipping 449 matching lines @@
     }
     CPDF_Dictionary* pElement = ToDictionary(pObj->GetDirect());
     if (!pElement)
       continue;
     if (pElement->GetStringBy("Type") != "Font")
       continue;
     CPDF_Font* pFind = pDocument->LoadFont(pElement);
     if (!pFind) {
       continue;
     }
-    CFX_SubstFont* pSubst = (CFX_SubstFont*)pFind->GetSubstFont();
+    CFX_SubstFont* pSubst = pFind->GetSubstFont();
     if (!pSubst) {
       continue;
     }
     if (pSubst->m_Charset == (int)charSet) {
       csNameTag = csKey;
       return pFind;
     }
   }
   return nullptr;
 }
 CPDF_Font* GetNativeInterFormFont(CPDF_Dictionary* pFormDict,
                                   CPDF_Document* pDocument,
                                   CFX_ByteString& csNameTag) {
   csNameTag = "";
   uint8_t charSet = CPDF_InterForm::GetNativeCharSet();
   CFX_SubstFont* pSubst;
   CPDF_Font* pFont = GetDefaultInterFormFont(pFormDict, pDocument);
   if (pFont) {
-    pSubst = (CFX_SubstFont*)pFont->GetSubstFont();
+    pSubst = pFont->GetSubstFont();
     if (pSubst && pSubst->m_Charset == (int)charSet) {
       FindInterFormFont(pFormDict, pFont, csNameTag);
       return pFont;
     }
   }
   return GetNativeInterFormFont(pFormDict, pDocument, charSet, csNameTag);
 }
 FX_BOOL FindInterFormFont(CPDF_Dictionary* pFormDict,
                           const CPDF_Font* pFont,
                           CFX_ByteString& csNameTag) {
@@ skipping 244 matching lines @@
   CPDF_Object* pAttr = pFieldDict->GetDirectObjectBy(name);
   if (pAttr) {
     return pAttr;
   }
   CPDF_Dictionary* pParent = pFieldDict->GetDictBy("Parent");
   if (!pParent) {
     return nullptr;
   }
   return FPDF_GetFieldAttr(pParent, name, nLevel + 1);
 }