Invalidate IPWL_FocusHandler and IPWL_Provider on destruction.

fpdfsdk/src/formfiller/FFL_TextField.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_TextField.h"
 
 #include "fpdfsdk/include/formfiller/FFL_CBA_Fontmap.h"
 #include "fpdfsdk/include/fsdk_common.h"
 #include "fpdfsdk/include/fsdk_mgr.h"
 
 CFFL_TextField::CFFL_TextField(CPDFDoc_Environment* pApp, CPDFSDK_Annot* pAnnot)
     : CFFL_FormFiller(pApp, pAnnot), m_pFontMap(NULL) {
   m_State.nStart = m_State.nEnd = 0;
 }
 
 CFFL_TextField::~CFFL_TextField() {
+  for (const auto& it : m_Maps)
+    it.second->InvalidateFocusHandler(this);
   delete m_pFontMap;
 }
 
 PWL_CREATEPARAM CFFL_TextField::GetCreateParam() {
   PWL_CREATEPARAM cp = CFFL_FormFiller::GetCreateParam();
 
   int nFlags = m_pWidget->GetFieldFlags();
 
   if (nFlags & FIELDFLAG_PASSWORD) {
     cp.dwFlags |= PES_PASSWORD;
@@ skipping 252 matching lines @@
     m_pApp->FFI_OnSetFieldInputFocus(m_pWidget->GetFormField(), pBuffer,
                                      nCharacters, TRUE);
 
     pEdit->SetEditNotify(this);
   }
 }
 
 void CFFL_TextField::OnKillFocus(CPWL_Wnd* pWnd) {}
 
 void CFFL_TextField::OnAddUndo(CPWL_Edit* pEdit) {}