Remove unused widget handler overrides

fpdfsdk/formfiller/cffl_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 "fpdfsdk/formfiller/cffl_listbox.h"
 
 #include "fpdfsdk/cpdfsdk_formfillenvironment.h"
 #include "fpdfsdk/cpdfsdk_widget.h"
@@ skipping 146 matching lines @@
         int32_t nCurSel = m_pWidget->GetSelectedIndex(0);
         if (nCurSel >= 0)
           fa.sValue = m_pWidget->GetOptionLabel(nCurSel);
       }
       break;
     default:
       break;
   }
 }
 
-void CFFL_ListBox::SetActionData(CPDFSDK_PageView* pPageView,
-                                 CPDF_AAction::AActionType type,
-                                 const PDFSDK_FieldAction& fa) {}
-
 void CFFL_ListBox::SaveState(CPDFSDK_PageView* pPageView) {
   ASSERT(pPageView);
 
   if (CPWL_ListBox* pListBox = (CPWL_ListBox*)GetPDFWindow(pPageView, FALSE)) {
     for (int32_t i = 0, sz = pListBox->GetCount(); i < sz; i++) {
       if (pListBox->IsItemSelected(i)) {
         m_State.Add(i);
       }
     }
   }
@@ skipping 19 matching lines @@
     RestoreState(pPageView);
     pRet = GetPDFWindow(pPageView, FALSE);
   } else {
     pRet = GetPDFWindow(pPageView, TRUE);
   }
 
   m_pWidget->UpdateField();
 
   return pRet;
 }