Add a fuzzer for CPDF_HintTables.

core/fpdfapi/fpdf_parser/cpdf_hint_tables.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_CPDF_HINT_TABLES_H_
 #define CORE_FPDFAPI_FPDF_PARSER_CPDF_HINT_TABLES_H_
 
 #include <vector>
 
 #include "core/fpdfapi/fpdf_parser/include/cpdf_data_avail.h"
 #include "core/fxcrt/include/fx_basic.h"
 #include "core/fxcrt/include/fx_stream.h"
 
 class CFX_BitStream;
 class CPDF_Dictionary;
 class CPDF_Stream;
 
 class CPDF_HintTables {
  public:
   CPDF_HintTables(CPDF_DataAvail* pDataAvail, CPDF_Dictionary* pLinearized);
-  ~CPDF_HintTables();
+  virtual ~CPDF_HintTables();
 
   bool GetPagePos(int index,
                   FX_FILESIZE* szPageStartPos,
                   FX_FILESIZE* szPageLength,
                   uint32_t* dwObjNum);
 
   CPDF_DataAvail::DocAvailStatus CheckPage(
       int index,
       CPDF_DataAvail::DownloadHints* pHints);
 
   bool LoadHintStream(CPDF_Stream* pHintStream);
 
  protected:
   bool ReadPageHintTable(CFX_BitStream* hStream);
   bool ReadSharedObjHintTable(CFX_BitStream* hStream, uint32_t offset);
   uint32_t GetItemLength(int index, const std::vector<FX_FILESIZE>& szArray);
 
  private:
-  int GetEndOfFirstPageOffset() const;
-  int GetNumberOfPages() const;
-  int GetFirstPageObjectNumber() const;
-  int GetFirstPageNumber() const;
-  int ReadPrimaryHintStreamOffset() const;
-  int ReadPrimaryHintStreamLength() const;
+  // Tests can override.
+  virtual int GetEndOfFirstPageOffset() const;
+  virtual int GetNumberOfPages() const;
+  virtual int GetFirstPageObjectNumber() const;
+  virtual int GetFirstPageNumber() const;
+  virtual int ReadPrimaryHintStreamOffset() const;
+  virtual int ReadPrimaryHintStreamLength() const;
 
   // Helper for the ReadPrimaryHintStream methods above.
   int ReadPrimaryHintStream(int index) const;
 
   // Owner, outlives this object.
   CPDF_DataAvail* const m_pDataAvail;
 
   // Owned by |m_pDataAvail|.
   CPDF_Dictionary* const m_pLinearizedDict;
 
   uint32_t m_nFirstPageSharedObjs;
   FX_FILESIZE m_szFirstPageObjOffset;
   std::vector<uint32_t> m_dwDeltaNObjsArray;
   std::vector<uint32_t> m_dwNSharedObjsArray;
   std::vector<uint32_t> m_dwSharedObjNumArray;
   std::vector<uint32_t> m_dwIdentifierArray;
   std::vector<FX_FILESIZE> m_szPageOffsetArray;
   std::vector<FX_FILESIZE> m_szSharedObjOffsetArray;
 };
 
 #endif  // CORE_FPDFAPI_FPDF_PARSER_CPDF_HINT_TABLES_H_