Clean compiling warnings on Linux (part2)

xfa/src/fxbarcode/datamatrix/BC_DataMatrixWriter.cpp

 // 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
 // Original code is licensed as follows:
 /*
  * Copyright 2008 ZXing authors
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ skipping 68 matching lines @@
   CBC_CommonByteMatrix* bytematrix = encodeLowLevel(placement, symbolInfo, e);
   BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
   outWidth = bytematrix->GetWidth();
   outHeight = bytematrix->GetHeight();
   uint8_t* result = FX_Alloc(uint8_t, outWidth * outHeight);
   FXSYS_memcpy(result, bytematrix->GetArray(), outWidth * outHeight);
   delete bytematrix;
   delete placement;
   return result;
 }
-uint8_t* CBC_DataMatrixWriter::Encode(const CFX_ByteString& contents,
-                                      BCFORMAT format,
-                                      int32_t& outWidth,
-                                      int32_t& outHeight,
-                                      int32_t& e) {
-  return NULL;
-}
-uint8_t* CBC_DataMatrixWriter::Encode(const CFX_ByteString& contents,
-                                      BCFORMAT format,
-                                      int32_t& outWidth,
-                                      int32_t& outHeight,
-                                      int32_t hints,
-                                      int32_t& e) {
-  return NULL;
-}
 CBC_CommonByteMatrix* CBC_DataMatrixWriter::encodeLowLevel(
     CBC_DefaultPlacement* placement,
     CBC_SymbolInfo* symbolInfo,
     int32_t& e) {
   int32_t symbolWidth = symbolInfo->getSymbolDataWidth(e);
   BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
   int32_t symbolHeight = symbolInfo->getSymbolDataHeight(e);
   BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
   CBC_CommonByteMatrix* matrix = new CBC_CommonByteMatrix(
       symbolInfo->getSymbolWidth(e), symbolInfo->getSymbolHeight(e));
@@ skipping 28 matching lines @@
       matrixX = 0;
       for (int32_t x = 0; x < symbolInfo->getSymbolWidth(e); x++) {
         matrix->Set(matrixX, matrixY, TRUE);
         matrixX++;
       }
       matrixY++;
     }
   }
   return matrix;
 }