Prevent base::CheckedNumeric from leaking outside of pdfium.

core/include/fxcrt/fx_stream.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 _FX_STREAM_H_
 #define _FX_STREAM_H_
 #ifndef _FX_MEMORY_H_
 #include "fx_memory.h"
@@ skipping 12 matching lines @@
 #include <unistd.h>
 #include <sys/stat.h>
 #ifndef O_BINARY
 #define O_BINARY                0
 #endif
 #ifndef O_LARGEFILE
 #define O_LARGEFILE             0
 #endif
 #define FX_FILESIZE                     off_t
 #endif
-typedef base::CheckedNumeric<FX_FILESIZE>    FX_SAFE_FILESIZE;
 #define FX_GETBYTEOFFSET32(a)   0
 #define FX_GETBYTEOFFSET40(a)   0
 #define FX_GETBYTEOFFSET48(a)   0
 #define FX_GETBYTEOFFSET56(a)   0
 #define FX_GETBYTEOFFSET24(a)  ((FX_BYTE)(a>>24))
 #define FX_GETBYTEOFFSET16(a)  ((FX_BYTE)(a>>16))
 #define FX_GETBYTEOFFSET8(a)   ((FX_BYTE)(a>>8))
 #define FX_GETBYTEOFFSET0(a)   ((FX_BYTE)(a))
 #define FX_FILEMODE_Write               0
 #define FX_FILEMODE_ReadOnly    1
@@ skipping 148 matching lines @@
 
     virtual FX_BOOL                     ReadNextBlock(FX_BOOL bRestart = FALSE) = 0;
 
     virtual FX_LPCBYTE          GetBlockBuffer() = 0;
 
     virtual size_t                      GetBlockSize() = 0;
 
     virtual FX_FILESIZE         GetBlockOffset() = 0;
 };
 #endif