Fix a leak in PDF_DataDecode() on failure.

core/src/fpdfapi/fpdf_parser/fpdf_parser_decode.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
 
 #include <limits.h>
 #include "../../../include/fpdfapi/fpdf_parser.h"
 #include "../../../include/fpdfapi/fpdf_module.h"
 #include "../../../include/fxcodec/fx_codec.h"
@@ skipping 398 matching lines @@
       ImageEncoding = decoder;
       pImageParms = pParam;
       dest_buf = (uint8_t*)last_buf;
       dest_size = last_size;
       return TRUE;
     }
     if (last_buf != src_buf) {
       FX_Free(last_buf);
     }
     if (offset == -1) {
+      FX_Free(new_buf);
       return FALSE;
     }
     last_buf = new_buf;
     last_size = new_size;
   }
   ImageEncoding = "";
   pImageParms = NULL;
   dest_buf = last_buf;
   dest_size = last_size;
   return TRUE;
@@ skipping 147 matching lines @@
                      FX_DWORD src_size,
                      uint8_t*& dest_buf,
                      FX_DWORD& dest_size) {
   CCodec_ModuleMgr* pEncoders = CPDF_ModuleMgr::Get()->GetCodecModule();
   if (pEncoders) {
     return pEncoders->GetFlateModule()->FlateOrLZWDecode(
         FALSE, src_buf, src_size, FALSE, 0, 0, 0, 0, 0, dest_buf, dest_size);
   }
   return 0;
 }