Remove { delete this; } anti-pattern from IXFA_WidgetIterator

fpdfsdk/fsdk_annothandler.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_annothandler.h"
 
 #include <algorithm>
 #include <vector>
@@ skipping 358 matching lines @@
   CPDFXFA_Page* pPage = pPageView->GetPDFXFAPage();
   if (pPage == NULL)
     return NULL;
   if (pPage->GetPDFPage()) {  // for pdf annots.
     CBA_AnnotIterator ai(pSDKAnnot->GetPageView(), pSDKAnnot->GetType(), "");
     CPDFSDK_Annot* pNext =
         bNext ? ai.GetNextAnnot(pSDKAnnot) : ai.GetPrevAnnot(pSDKAnnot);
     return pNext;
   }
   // for xfa annots
-  IXFA_WidgetIterator* pWidgetIterator =
+  std::unique_ptr<IXFA_WidgetIterator> pWidgetIterator(
       pPage->GetXFAPageView()->CreateWidgetIterator(
           XFA_TRAVERSEWAY_Tranvalse, XFA_WIDGETFILTER_Visible |
                                          XFA_WIDGETFILTER_Viewable |
-                                         XFA_WIDGETFILTER_Field);
-  if (pWidgetIterator == NULL)
-    return NULL;
+                                         XFA_WIDGETFILTER_Field));
+  if (!pWidgetIterator)
+    return nullptr;
   if (pWidgetIterator->GetCurrentWidget() != pSDKAnnot->GetXFAWidget())
     pWidgetIterator->SetCurrentWidget(pSDKAnnot->GetXFAWidget());
-  CXFA_FFWidget* hNextFocus = NULL;
-  hNextFocus =
+  CXFA_FFWidget* hNextFocus =
       bNext ? pWidgetIterator->MoveToNext() : pWidgetIterator->MoveToPrevious();
   if (!hNextFocus && pSDKAnnot)
     hNextFocus = pWidgetIterator->MoveToFirst();
 
-  pWidgetIterator->Release();
   return pPageView->GetAnnotByXFAWidget(hNextFocus);
 #else   // PDF_ENABLE_XFA
   CBA_AnnotIterator ai(pSDKAnnot->GetPageView(), "Widget", "");
   return bNext ? ai.GetNextAnnot(pSDKAnnot) : ai.GetPrevAnnot(pSDKAnnot);
 #endif  // PDF_ENABLE_XFA
 }
 
 FX_BOOL CPDFSDK_BFAnnotHandler::CanAnswer(CPDFSDK_Annot* pAnnot) {
   ASSERT(pAnnot->GetType() == "Widget");
   if (pAnnot->GetSubType() == BFFT_SIGNATURE)
@@ skipping 688 matching lines @@
 
 CPDFSDK_Annot* CPDFSDK_AnnotIterator::PrevAnnot() {
   if (m_pos < m_iteratorAnnotList.size())
     return m_iteratorAnnotList[m_iteratorAnnotList.size() - ++m_pos];
   return nullptr;
 }
 
 CPDFSDK_Annot* CPDFSDK_AnnotIterator::Next() {
   return m_bReverse ? PrevAnnot() : NextAnnot();
 }