Get rid of NULLs in xfa/

xfa/fwl/lightwidget/cfwl_listbox.h

Index: xfa/fwl/lightwidget/cfwl_listbox.h
diff --git a/xfa/fwl/lightwidget/cfwl_listbox.h b/xfa/fwl/lightwidget/cfwl_listbox.h
index 7d79893fa6ef6204a52445c4e9c805bff8da6952..df5d122f60976d88a46bea9b347d95a8c14ef97b 100644
--- a/xfa/fwl/lightwidget/cfwl_listbox.h
+++ b/xfa/fwl/lightwidget/cfwl_listbox.h
@@ -20,7 +20,7 @@ class CFWL_ListItem;
 class CFWL_ListBox : public CFWL_Widget {
  public:
   static CFWL_ListBox* Create();
-  FWL_Error Initialize(const CFWL_WidgetProperties* pProperties = NULL);
+  FWL_Error Initialize(const CFWL_WidgetProperties* pProperties = nullptr);
   FWL_Error AddDIBitmap(CFX_DIBitmap* pDIB, IFWL_ListItem* pItem);
   IFWL_ListItem* AddString(const CFX_WideStringC& wsAdd,
                            FX_BOOL bSelect = FALSE);
@@ -109,8 +109,8 @@ class CFWL_ListItem : public IFWL_ListItem {
     m_rtItem.Reset();
     m_dwStates = 0;
     m_wsText = L"";
-    m_pDIB = NULL;
-    m_pData = NULL;
+    m_pDIB = nullptr;
+    m_pData = nullptr;
     m_dwCheckState = 0;
     m_rtCheckBox.Reset();
   }