Use some FXSYS methods instead of duplicating

core/fxcrt/include/fx_ext.h

 // 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
 
 #ifndef CORE_FXCRT_INCLUDE_FX_EXT_H_
 #define CORE_FXCRT_INCLUDE_FX_EXT_H_
 
 #include <cctype>
@@ skipping 35 matching lines @@
 }
 inline bool FXSYS_iswalpha(wchar_t wch) {
   return (wch >= L'A' && wch <= L'Z') || (wch >= L'a' && wch <= L'z');
 }
 inline bool FXSYS_iswdigit(wchar_t wch) {
   return wch >= L'0' && wch <= L'9';
 }
 inline bool FXSYS_iswalnum(wchar_t wch) {
   return FXSYS_iswalpha(wch) || FXSYS_iswdigit(wch);
 }
+inline bool FXSYS_iswspace(FX_WCHAR c) {
+  return (c == 0x20) || (c == 0x0d) || (c == 0x0a) || (c == 0x09);
+}
 
 inline int FXSYS_toHexDigit(const FX_CHAR c) {
   if (!std::isxdigit(c))
     return 0;
   char upchar = std::toupper(c);
   return upchar > '9' ? upchar - 'A' + 10 : upchar - '0';
 }
 
 inline bool FXSYS_isDecimalDigit(const FX_CHAR c) {
   return !!std::isdigit(c);
 }
 
 inline bool FXSYS_isDecimalDigit(const FX_WCHAR c) {
   return !!std::iswdigit(c);
 }
 
 inline int FXSYS_toDecimalDigit(const FX_CHAR c) {
   return std::isdigit(c) ? c - '0' : 0;
 }
 
 inline int FXSYS_toDecimalDigit(const FX_WCHAR c) {
   return std::iswdigit(c) ? c - L'0' : 0;
 }
 
+FX_FLOAT FXSYS_FractionalScale(size_t scale_factor, int value);
+int FXSYS_FractionalScaleCount();
+
 uint32_t FX_HashCode_GetA(const CFX_ByteStringC& str, bool bIgnoreCase);
 uint32_t FX_HashCode_GetW(const CFX_WideStringC& Str, bool bIgnoreCase);
 
 void* FX_Random_MT_Start(uint32_t dwSeed);
 
 uint32_t FX_Random_MT_Generate(void* pContext);
 
 void FX_Random_MT_Close(void* pContext);
 
 void FX_Random_GenerateBase(uint32_t* pBuffer, int32_t iCount);
@@ skipping 33 matching lines @@
           j -= gap;
         }
         pArray[j + gap] = v1;
       }
       gap >>= 1;
     }
   }
 };
 
 #endif  // CORE_FXCRT_INCLUDE_FX_EXT_H_