Revert of Remove pageview from map immediately

fpdfsdk/fsdk_mgr.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/fsdk_mgr.h"
 
 #include <algorithm>
 #include <memory>
@@ skipping 335 matching lines @@
 
 void CPDFSDK_Document::RemovePageView(UnderlyingPageType* pUnderlyingPage) {
   auto it = m_pageMap.find(pUnderlyingPage);
   if (it == m_pageMap.end())
     return;
 
   CPDFSDK_PageView* pPageView = it->second;
   if (pPageView->IsLocked())
     return;
 
-  // Remove the page from the map to make sure we don't accidentally attempt
-  // to use the |pPageView| while we're cleaning it up.
-  m_pageMap.erase(it);
-
   pPageView->KillFocusAnnotIfNeeded();
   delete pPageView;
+  m_pageMap.erase(it);
 }
 
 UnderlyingPageType* CPDFSDK_Document::GetPage(int nIndex) {
   return UnderlyingFromFPDFPage(m_pEnv->FFI_GetPage(m_pDoc, nIndex));
 }
 
 CPDFSDK_InterForm* CPDFSDK_Document::GetInterForm() {
   if (!m_pInterForm)
     m_pInterForm.reset(new CPDFSDK_InterForm(this));
   return m_pInterForm.get();
@@ skipping 674 matching lines @@
 int CPDFSDK_PageView::GetPageIndexForStaticPDF() const {
 #ifdef PDF_ENABLE_XFA
   CPDF_Page* pPage = m_page->GetPDFPage();
 #else   // PDF_ENABLE_XFA
   CPDF_Page* pPage = m_page;
 #endif  // PDF_ENABLE_XFA
   CPDF_Dictionary* pDict = pPage->m_pFormDict;
   CPDF_Document* pDoc = m_pSDKDoc->GetPDFDocument();
   return (pDoc && pDict) ? pDoc->GetPageIndex(pDict->GetObjNum()) : -1;
 }