Use some FXSYS methods instead of duplicating

xfa/fxfa/parser/xfa_utils_imp.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 "xfa/fxfa/parser/xfa_utils.h"
 
 #include "core/fxcrt/include/fx_ext.h"
 #include "xfa/fde/xml/fde_xml_imp.h"
@@ skipping 285 matching lines @@
   } else if (str[0] == '-') {
     bNegative = TRUE;
     cc++;
   }
   int32_t nIntegralLen = 0;
   while (cc < len) {
     if (str[cc] == '.' || str[cc] == 'E' || str[cc] == 'e' ||
         nIntegralLen > 17) {
       break;
     }
-    if (!XFA_IsDigit(str[cc])) {
+    if (!FXSYS_isDecimalDigit(str[cc])) {
       return 0;
     }
     nIntegral = nIntegral * 10 + str[cc] - '0';
     cc++;
     nIntegralLen++;
   }
   nIntegral = bNegative ? -nIntegral : nIntegral;
   int32_t scale = 0;
   FX_DOUBLE fraction = 0.0;
   if (cc < len && str[cc] == '.') {
     cc++;
     while (cc < len) {
       fraction += fraction_scales[scale] * (str[cc] - '0');
       scale++;
       cc++;
       if (cc == len) {
         break;
       }
       if (scale == sizeof(fraction_scales) / sizeof(FX_DOUBLE) ||
           str[cc] == 'E' || str[cc] == 'e') {
         break;
       }
-      if (!XFA_IsDigit(str[cc])) {
+      if (!FXSYS_isDecimalDigit(str[cc])) {
         return 0;
       }
     }
     dwFractional = (uint32_t)(fraction * 4294967296.0);
   }
   if (cc < len && (str[cc] == 'E' || str[cc] == 'e')) {
     cc++;
     if (cc < len) {
       if (str[cc] == '+') {
         cc++;
       } else if (str[cc] == '-') {
         bExpSign = TRUE;
         cc++;
       }
     }
     while (cc < len) {
-      if (str[cc] == '.' || !XFA_IsDigit(str[cc])) {
+      if (str[cc] == '.' || !FXSYS_isDecimalDigit(str[cc])) {
         return 0;
       }
       nExponent = nExponent * 10 + str[cc] - '0';
       cc++;
     }
     nExponent = bExpSign ? -nExponent : nExponent;
   }
   FX_DOUBLE dValue = (dwFractional / 4294967296.0);
   dValue = nIntegral + (nIntegral >= 0 ? dValue : -dValue);
   if (nExponent != 0) {
     dValue *= FXSYS_pow(10, (FX_FLOAT)nExponent);
   }
   return dValue;
 }
 
 FX_DOUBLE XFA_ByteStringToDouble(const CFX_ByteStringC& szStringVal) {
   CFX_WideString wsValue = CFX_WideString::FromUTF8(szStringVal);
   return XFA_WideStringToDouble(wsValue);
 }
 
 int32_t XFA_MapRotation(int32_t nRotation) {
   nRotation = nRotation % 360;
   nRotation = nRotation < 0 ? nRotation + 360 : nRotation;
   return nRotation;
 }