Remove FX_DWORD from core/ and delete definition

core/fxcodec/jbig2/JBig2_PatternDict.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 "core/fxcodec/jbig2/JBig2_PatternDict.h"
 
 #include "core/fxcrt/include/fx_memory.h"
 
 CJBig2_PatternDict::CJBig2_PatternDict() {
   NUMPATS = 0;
   HDPATS = NULL;
 }
 
 CJBig2_PatternDict::~CJBig2_PatternDict() {
   if (HDPATS) {
-    for (FX_DWORD i = 0; i < NUMPATS; i++) {
+    for (uint32_t i = 0; i < NUMPATS; i++) {
       delete HDPATS[i];
     }
     FX_Free(HDPATS);
   }
 }