Reduce duplicated code in CPDF_Document by adding auxiliary methods

core/fpdfapi/fpdf_parser/include/cpdf_document.h

 // Copyright 2016 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
 
 #ifndef CORE_FPDFAPI_FPDF_PARSER_INCLUDE_CPDF_DOCUMENT_H_
 #define CORE_FPDFAPI_FPDF_PARSER_INCLUDE_CPDF_DOCUMENT_H_
 
+#include <functional>
 #include <memory>
 
 #include "core/fpdfapi/fpdf_parser/include/cpdf_indirect_object_holder.h"
 #include "core/fpdfapi/fpdf_parser/include/cpdf_object.h"
 #include "core/fpdfdoc/include/cpdf_linklist.h"
 #include "core/fxcrt/include/fx_basic.h"
 
 class CFX_Font;
 class CFX_Matrix;
 class CPDF_ColorSpace;
@@ skipping 101 matching lines @@
   // TODO(thestig): Figure out why this cannot be a std::unique_ptr.
   CPDF_DocPageData* m_pDocPage;
   std::unique_ptr<CPDF_DocRenderData> m_pDocRender;
   std::unique_ptr<JBig2_DocumentContext> m_pCodecContext;
   std::unique_ptr<CPDF_LinkList> m_pLinksContext;
 
  private:
   void LoadDocInternal();
   size_t CalculateEncodingDict(int charset, CPDF_Dictionary* pBaseDict);
   CPDF_Dictionary* GetPagesDict() const;
+  CPDF_Dictionary* ProcessbCJK(
+      CPDF_Dictionary* pBaseDict,
+      int charset,
+      FX_BOOL bVert,
+      CFX_ByteString basefont,
+      std::function<void(FX_WCHAR, FX_WCHAR, CPDF_Array*)> Insert);
 };
 
 #endif  // CORE_FPDFAPI_FPDF_PARSER_INCLUDE_CPDF_DOCUMENT_H_