Cleanup widget edge related code

xfa/fwl/cfwl_listbox.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 "xfa/fwl/cfwl_listbox.h"
 
 #include <algorithm>
 #include <memory>
@@ skipping 84 matching lines @@
                               const CFX_Matrix* pMatrix) {
   if (!pGraphics)
     return;
   if (!m_pProperties->m_pThemeProvider)
     return;
 
   IFWL_ThemeProvider* pTheme = m_pProperties->m_pThemeProvider;
   pGraphics->SaveGraphState();
   if (HasBorder())
     DrawBorder(pGraphics, CFWL_Part::Border, pTheme, pMatrix);
-  if (HasEdge())
-    DrawEdge(pGraphics, CFWL_Part::Edge, pTheme, pMatrix);
 
   CFX_RectF rtClip(m_rtConent);
   if (IsShowScrollBar(false))
     rtClip.height -= m_fScorllBarWidth;
   if (IsShowScrollBar(true))
     rtClip.width -= m_fScorllBarWidth;
   if (pMatrix)
     pMatrix->TransformRect(rtClip);
 
   pGraphics->SetClipRect(rtClip);
@@ skipping 831 matching lines @@
     if (CFWL_ListItem* item = GetItem(this, iSel))
       item->SetStates(item->GetStates() | FWL_ITEMSTATE_LTB_Selected);
   }
 
   m_ItemArray.erase(m_ItemArray.begin() + nIndex);
 }
 
 void CFWL_ListBox::DeleteAll() {
   m_ItemArray.clear();
 }