Invalidate IPWL_FocusHandler and IPWL_Provider on destruction.

fpdfsdk/src/formfiller/FFL_ComboBox.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/include/formfiller/FFL_ComboBox.h"
 
 #include "fpdfsdk/include/formfiller/FFL_CBA_Fontmap.h"
 #include "fpdfsdk/include/formfiller/FFL_FormFiller.h"
 #include "fpdfsdk/include/formfiller/FFL_IFormFiller.h"
 #include "fpdfsdk/include/fsdk_common.h"
 #include "fpdfsdk/include/fsdk_mgr.h"
 #include "fpdfsdk/include/pdfwindow/PWL_ComboBox.h"
 
 CFFL_ComboBox::CFFL_ComboBox(CPDFDoc_Environment* pApp, CPDFSDK_Annot* pAnnot)
     : CFFL_FormFiller(pApp, pAnnot), m_pFontMap(NULL) {
   m_State.nIndex = 0;
   m_State.nStart = 0;
   m_State.nEnd = 0;
 }
 
 CFFL_ComboBox::~CFFL_ComboBox() {
+  for (const auto& it : m_Maps)
+    it.second->InvalidateFocusHandler(this);
   delete m_pFontMap;
 }
 
 PWL_CREATEPARAM CFFL_ComboBox::GetCreateParam() {
   PWL_CREATEPARAM cp = CFFL_FormFiller::GetCreateParam();
 
   int nFlags = m_pWidget->GetFieldFlags();
   if (nFlags & FIELDFLAG_EDIT) {
     cp.dwFlags |= PCBS_ALLOWCUSTOMTEXT;
   }
@@ skipping 257 matching lines @@
   if (nExport >= 0) {
     if (CPDF_FormField* pFormField = m_pWidget->GetFormField()) {
       swRet = pFormField->GetOptionValue(nExport);
       if (swRet.IsEmpty())
         swRet = pFormField->GetOptionLabel(nExport);
     }
   }
 
   return swRet;
 }