Remove PageObject's m_Type and add As<Type> functions

core/src/fpdfapi/fpdf_render/fpdf_render_image.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/src/fpdfapi/fpdf_render/render_int.h"
 
 #include <utility>
 #include <vector>
 
 #include "core/include/fpdfapi/fpdf_module.h"
 #include "core/include/fpdfapi/fpdf_pageobj.h"
 #include "core/include/fpdfapi/fpdf_render.h"
 #include "core/include/fxcodec/fx_codec.h"
 #include "core/include/fxcrt/fx_safe_types.h"
 #include "core/include/fxge/fx_ge.h"
 #include "core/src/fpdfapi/fpdf_page/pageint.h"
 
-FX_BOOL CPDF_RenderStatus::ProcessImage(CPDF_ImageObject* pImageObj,
+FX_BOOL CPDF_RenderStatus::ProcessImage(const CPDF_ImageObject* pImageObj,
                                         const CFX_Matrix* pObj2Device) {
   CPDF_ImageRenderer render;
   if (render.Start(this, pImageObj, pObj2Device, m_bStdCS, m_curBlend)) {
     render.Continue(NULL);
   }
   return render.m_Result;
 }
 void CPDF_RenderStatus::CompositeDIBitmap(CFX_DIBitmap* pDIBitmap,
                                           int left,
                                           int top,
@@ skipping 954 matching lines @@
   } else if (pFunc) {
     int size = dest_pitch * height;
     for (int i = 0; i < size; i++) {
       dest_buf[i] = transfers[src_buf[i]];
     }
   } else {
     FXSYS_memcpy(dest_buf, src_buf, dest_pitch * height);
   }
   return pMask.release();
 }