Cleanup widget edge related code

xfa/fwl/theme/cfwl_listboxtp.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/theme/cfwl_listboxtp.h"
 
 #include "xfa/fwl/cfwl_listbox.h"
 #include "xfa/fwl/cfwl_themebackground.h"
@@ skipping 11 matching lines @@
 
 void CFWL_ListBoxTP::DrawBackground(CFWL_ThemeBackground* pParams) {
   if (!pParams)
     return;
 
   switch (pParams->m_iPart) {
     case CFWL_Part::Border: {
       DrawBorder(pParams->m_pGraphics, &pParams->m_rtPart, &pParams->m_matrix);
       break;
     }
-    case CFWL_Part::Edge: {
-      DrawEdge(pParams->m_pGraphics, pParams->m_pWidget->GetStyles(),
-               &pParams->m_rtPart, &pParams->m_matrix);
-      break;
-    }
     case CFWL_Part::Background: {
       FillSoildRect(pParams->m_pGraphics, ArgbEncode(255, 255, 255, 255),
                     &pParams->m_rtPart, &pParams->m_matrix);
       if (pParams->m_pData) {
         FillSoildRect(pParams->m_pGraphics, FWLTHEME_COLOR_Background,
                       (CFX_RectF*)pParams->m_pData, &pParams->m_matrix);
       }
       break;
     }
     case CFWL_Part::ListItem: {
@@ skipping 47 matching lines @@
     path.AddRectangle(rt.left, rt.top, rt.width - 1, rt.height - 1);
 #else
     path.AddRectangle(rt.left, rt.top, rt.width, rt.height);
 #endif
     pGraphics->FillPath(&path, FXFILL_WINDING, pMatrix);
     pGraphics->RestoreGraphState();
   }
   if (dwStates & CFWL_PartState_Focused && pData)
     DrawFocus(pGraphics, (CFX_RectF*)pData, pMatrix);
 }