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

core/src/fpdfapi/fpdf_edit/fpdf_edit_content.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/include/fpdfapi/fpdf_module.h"
 #include "core/include/fpdfapi/fpdf_page.h"
 #include "core/include/fpdfapi/fpdf_serial.h"
 #include "core/src/fpdfapi/fpdf_page/pageint.h"
@@ skipping 38 matching lines @@
     pPageDict->RemoveAt("Contents");
   }
   CPDF_Stream* pStream = new CPDF_Stream(NULL, 0, NULL);
   pStream->SetData(buf.GetBuffer(), buf.GetLength(), FALSE, FALSE);
   m_pDocument->AddIndirectObject(pStream);
   pPageDict->SetAtReference("Contents", m_pDocument, pStream->GetObjNum());
 }
 CFX_ByteString CPDF_PageContentGenerate::RealizeResource(
     CPDF_Object* pResourceObj,
     const FX_CHAR* szType) {
-  if (m_pPage->m_pResources == NULL) {
+  if (!m_pPage->m_pResources) {
     m_pPage->m_pResources = new CPDF_Dictionary;
     int objnum = m_pDocument->AddIndirectObject(m_pPage->m_pResources);
     m_pPage->m_pFormDict->SetAtReference("Resources", m_pDocument, objnum);
   }
   CPDF_Dictionary* pResList = m_pPage->m_pResources->GetDict(szType);
-  if (pResList == NULL) {
+  if (!pResList) {
     pResList = new CPDF_Dictionary;
     m_pPage->m_pResources->SetAt(szType, pResList);
   }
   m_pDocument->AddIndirectObject(pResourceObj);
   CFX_ByteString name;
   int idnum = 1;
   while (1) {
     name.Format("FX%c%d", szType[0], idnum);
     if (!pResList->KeyExist(name)) {
       break;
@@ skipping 80 matching lines @@
     CPDF_StreamAcc contentStream;
     contentStream.LoadAllData(pStream);
     ProcessForm(buf, contentStream.GetData(), contentStream.GetSize(), matrix);
   }
   CPDF_Stream* pStream = new CPDF_Stream(NULL, 0, NULL);
   pStream->SetData(buf.GetBuffer(), buf.GetLength(), FALSE, FALSE);
   m_pDocument->AddIndirectObject(pStream);
   m_pPage->m_pFormDict->SetAtReference("Contents", m_pDocument,
                                        pStream->GetObjNum());
 }