Get rid of most instance of 'foo != NULL'

core/src/fpdfapi/fpdf_page/fpdf_page_parser_old.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 "pageint.h"
 
 #include <limits.h>
 
@@ skipping 331 matching lines @@
       if (pParams)
         pParam = pParams->GetDict(0);
     } else {
       Decoder = pFilter->GetString();
       pParam = pDict->GetDict("DecodeParms");
     }
   }
   FX_DWORD width = pDict->GetInteger("Width");
   FX_DWORD height = pDict->GetInteger("Height");
   FX_DWORD OrigSize = 0;
-  if (pCSObj != NULL) {
+  if (pCSObj) {
     FX_DWORD bpc = pDict->GetInteger("BitsPerComponent");
     FX_DWORD nComponents = 1;
     CPDF_ColorSpace* pCS = pDoc->LoadColorSpace(pCSObj);
     if (pCS == NULL) {
       nComponents = 3;
     } else {
       nComponents = pCS->CountComponents();
       pDoc->GetPageData()->ReleaseColorSpace(pCSObj);
     }
     FX_DWORD pitch = width;
@@ skipping 757 matching lines @@
       }
       m_Status = Done;
       return;
     }
     steps++;
     if (pPause && pPause->NeedToPauseNow()) {
       break;
     }
   }
 }