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

fpdfsdk/src/fpdf_transformpage.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 "public/fpdf_transformpage.h"
 
 #include "fpdfsdk/include/fsdk_define.h"
 
@@ skipping 182 matching lines @@
                               double e,
                               double f) {
   CPDF_PageObject* pPageObj = (CPDF_PageObject*)page_object;
   if (!pPageObj)
     return;
   CFX_Matrix matrix((FX_FLOAT)a, (FX_FLOAT)b, (FX_FLOAT)c, (FX_FLOAT)d,
                     (FX_FLOAT)e, (FX_FLOAT)f);
 
   // Special treatment to shading object, because the ClipPath for shading
   // object is already transformed.
-  if (pPageObj->m_Type != CPDF_PageObject::SHADING)
+  if (!pPageObj->IsShading())
     pPageObj->TransformClipPath(matrix);
   pPageObj->TransformGeneralState(matrix);
 }
 
 DLLEXPORT FPDF_CLIPPATH STDCALL FPDF_CreateClipPath(float left,
                                                     float bottom,
                                                     float right,
                                                     float top) {
   CPDF_ClipPath* pNewClipPath = new CPDF_ClipPath();
   pNewClipPath->GetModify();
@@ skipping 100 matching lines @@
       } else if (pDirectObj->IsStream()) {
         pContentArray = new CPDF_Array();
         pContentArray->AddReference(pDoc, pStream->GetObjNum());
         pContentArray->AddReference(pDoc, pDirectObj->GetObjNum());
         pPageDic->SetAtReference("Contents", pDoc,
                                  pDoc->AddIndirectObject(pContentArray));
       }
     }
   }
 }