Remove custom memory manager

core/src/fxge/dib/fx_dib_main.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 "../../../include/fxge/fx_dib.h"
 #include "../../../include/fxge/fx_ge.h"
 #include "../../../include/fxcodec/fx_codec.h"
 #include "dib_int.h"
@@ skipping 73 matching lines @@
         int size = pitch * height + 4;
         int oomlimit = _MAX_OOM_LIMIT_;
         if (oomlimit >= 0 && size >= oomlimit) {
             m_pBuffer = FX_AllocNL(FX_BYTE, size);
         } else {
             m_pBuffer = FX_Alloc(FX_BYTE, size);
         }
         if (m_pBuffer == NULL) {
             return FALSE;
         }
-        FXSYS_memset32(m_pBuffer, 0, sizeof (FX_BYTE) * size);
     }
     m_Width = width;
     m_Height = height;
     m_Pitch = pitch;
     if (HasAlpha() && format != FXDIB_Argb) {
         FX_BOOL ret = TRUE;
         ret = BuildAlphaMask();
         if (!ret) {
             if (!m_bExtBuf && m_pBuffer) {
                 FX_Free(m_pBuffer);
@@ skipping 1621 matching lines @@
     if (!m_pBitmap->Create(width, height, src_format)) {
         delete m_pBitmap;
         m_pBitmap = NULL;
         return FALSE;
     }
     if (pSrcPalette) {
         m_pBitmap->CopyPalette(pSrcPalette);
     }
     return TRUE;
 }