Remove dead code found by Scythe.

core/src/fxcodec/codec/codec_int.h

 // 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
 
 #ifndef CORE_SRC_FXCODEC_CODEC_CODEC_INT_H_
 #define CORE_SRC_FXCODEC_CODEC_CODEC_INT_H_
 
 #include <limits.h>
@@ skipping 226 matching lines @@
     virtual void JBig2_Free(void* pMem)
     {
         FX_Free(pMem);
     }
 };
 class CCodec_Jbig2Context
 {
 public:
     CCodec_Jbig2Context();
     ~CCodec_Jbig2Context() {};
-    IFX_FileRead* m_file_ptr;
+
     FX_DWORD m_width;
     FX_DWORD m_height;
     uint8_t* m_src_buf;
     FX_DWORD m_src_size;
     const uint8_t* m_global_data;
     FX_DWORD m_global_size;
     uint8_t* m_dest_buf;
     FX_DWORD m_dest_pitch;
     FX_BOOL     m_bFileReader;
     IFX_Pause* m_pPause;
@@ skipping 32 matching lines @@
     OPJ_SIZE_T     offset;
 };
 
 /* Wrappers for C-style callbacks. */
 OPJ_SIZE_T opj_read_from_memory (void* p_buffer, OPJ_SIZE_T nb_bytes,  void* p_user_data);
 OPJ_SIZE_T opj_write_from_memory (void* p_buffer, OPJ_SIZE_T nb_bytes, void* p_user_data);
 OPJ_OFF_T opj_skip_from_memory (OPJ_OFF_T nb_bytes, void* p_user_data);
 OPJ_BOOL opj_seek_from_memory (OPJ_OFF_T nb_bytes, void* p_user_data);
 
 #endif  // CORE_SRC_FXCODEC_CODEC_CODEC_INT_H_