Convert loose FX_Create* functions into static methods

xfa/fxfa/app/xfa_ffwidget.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/xfa_ffwidget.h"
 
 #include <algorithm>
 #include <memory>
@@ skipping 1048 matching lines @@
   IFX_SeekableReadStream* pImageFileRead = nullptr;
   if (wsImage.GetLength() > 0) {
     XFA_ATTRIBUTEENUM iEncoding =
         (XFA_ATTRIBUTEENUM)pImage->GetTransferEncoding();
     if (iEncoding == XFA_ATTRIBUTEENUM_Base64) {
       CFX_ByteString bsData = wsImage.UTF8Encode();
       int32_t iLength = bsData.GetLength();
       pImageBuffer = FX_Alloc(uint8_t, iLength);
       int32_t iRead = XFA_Base64Decode(bsData.c_str(), pImageBuffer);
       if (iRead > 0) {
-        pImageFileRead = FX_CreateMemoryStream(pImageBuffer, iRead);
+        pImageFileRead = IFX_MemoryStream::Create(pImageBuffer, iRead);
       }
     } else {
       bsContent = CFX_ByteString::FromUnicode(wsImage);
-      pImageFileRead = FX_CreateMemoryStream(
+      pImageFileRead = IFX_MemoryStream::Create(
           const_cast<uint8_t*>(bsContent.raw_str()), bsContent.GetLength());
     }
   } else {
     CFX_WideString wsURL = wsHref;
     if (wsURL.Left(7) != FX_WSTRC(L"http://") &&
         wsURL.Left(6) != FX_WSTRC(L"ftp://")) {
       CFX_DIBitmap* pBitmap =
           pDoc->GetPDFNamedImage(wsURL.AsStringC(), iImageXDpi, iImageYDpi);
       if (pBitmap) {
         bNameImage = true;
@@ skipping 961 matching lines @@
   }
   XFA_BOX_Fill(box, strokes, pGS, rtWidget, pMatrix, dwFlags);
   XFA_BOX_Stroke(box, strokes, pGS, rtWidget, pMatrix, dwFlags);
 }
 
 CXFA_CalcData::CXFA_CalcData() : m_iRefCount(0) {}
 
 CXFA_CalcData::~CXFA_CalcData() {
   m_Globals.RemoveAll();
 }