Move ByteStringPool from document to indirect object holder.

core/fpdfapi/parser/cfdf_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_PARSER_CFDF_DOCUMENT_H_
 #define CORE_FPDFAPI_PARSER_CFDF_DOCUMENT_H_
 
 #include "core/fpdfapi/parser/cpdf_indirect_object_holder.h"
 #include "core/fpdfapi/parser/cpdf_object.h"
-#include "core/fxcrt/cfx_string_pool_template.h"
-#include "core/fxcrt/cfx_weak_ptr.h"
 #include "core/fxcrt/fx_basic.h"
 
 class CPDF_Dictionary;
 
 class CFDF_Document : public CPDF_IndirectObjectHolder {
  public:
   static CFDF_Document* CreateNewDoc();
   static CFDF_Document* ParseFile(IFX_SeekableReadStream* pFile,
                                   bool bOwnFile = false);
   static CFDF_Document* ParseMemory(const uint8_t* pData, uint32_t size);
   ~CFDF_Document() override;
 
   bool WriteBuf(CFX_ByteTextBuf& buf) const;
   CPDF_Dictionary* GetRoot() const { return m_pRootDict; }
-  CFX_WeakPtr<CFX_ByteStringPool> GetByteStringPool() const {
-    return m_pByteStringPool;
-  }
 
  protected:
   CFDF_Document();
   void ParseStream(IFX_SeekableReadStream* pFile, bool bOwnFile);
 
   CPDF_Dictionary* m_pRootDict;
   IFX_SeekableReadStream* m_pFile;
   bool m_bOwnFile;
-  CFX_WeakPtr<CFX_ByteStringPool> m_pByteStringPool;
 };
 
 #endif  // CORE_FPDFAPI_PARSER_CFDF_DOCUMENT_H_