Fix all relative includes to third_party.

core/src/fxcodec/codec/fx_codec_jpeg.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 <setjmp.h>
 
 #include "../../../include/fxcodec/fx_codec.h"
 #include "../../../include/fxcrt/fx_safe_types.h"
 #include "../../../include/fxge/fx_dib.h"
 #include "codec_int.h"
 
 extern "C" {
 #undef FAR
-#include "../../../../third_party/libjpeg/jpeglib.h"
+#if defined(USE_SYSTEM_LIBJPEG)
+#include <jpeglib.h>
+#elif defined(USE_LIBJPEG_TURBO)
+#include "third_party/libjpeg_turbo/jpeglib.h"
+#else
+#include "third_party/libjpeg/jpeglib.h"
+#endif
 }
 
 extern "C" {
 static void _JpegScanSOI(const uint8_t*& src_buf, FX_DWORD& src_size) {
   if (src_size == 0) {
     return;
   }
   FX_DWORD offset = 0;
   while (offset < src_size - 1) {
     if (src_buf[offset] == 0xff && src_buf[offset + 1] == 0xd8) {
@@ skipping 619 matching lines @@
                                           uint8_t** avail_buf_ptr) {
   if (avail_buf_ptr != NULL) {
     *avail_buf_ptr = NULL;
     if (((FXJPEG_Context*)pContext)->m_SrcMgr.bytes_in_buffer > 0) {
       *avail_buf_ptr =
           (uint8_t*)((FXJPEG_Context*)pContext)->m_SrcMgr.next_input_byte;
     }
   }
   return (FX_DWORD)((FXJPEG_Context*)pContext)->m_SrcMgr.bytes_in_buffer;
 }