Remove Release() from IFX_CharIter, use unique_ptrs.

xfa/fee/fde_txtedtbuf.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 "xfa/fee/fde_txtedtbuf.h"
 
 #include <algorithm>
 
@@ skipping 11 matching lines @@
 #define FDE_TXTEDT_ZEROWIDTHSPACE 0x200B
 
 CFDE_TxtEdtBufIter::CFDE_TxtEdtBufIter(CFDE_TxtEdtBuf* pBuf, FX_WCHAR wcAlias)
     : m_pBuf(pBuf),
       m_nCurChunk(0),
       m_nCurIndex(0),
       m_nIndex(0),
       m_Alias(wcAlias) {
   ASSERT(m_pBuf);
 }
+
 CFDE_TxtEdtBufIter::~CFDE_TxtEdtBufIter() {}
-void CFDE_TxtEdtBufIter::Release() {
-  delete this;
-}
+
 FX_BOOL CFDE_TxtEdtBufIter::Next(FX_BOOL bPrev) {
   if (bPrev) {
     if (m_nIndex == 0) {
       return FALSE;
     }
     ASSERT(m_nCurChunk < m_pBuf->m_Chunks.GetSize());
     CFDE_TxtEdtBuf::FDE_CHUNKHEADER* lpChunk = nullptr;
     if (m_nCurIndex > 0) {
       m_nCurIndex--;
     } else {
@@ skipping 351 matching lines @@
   int32_t nCount = m_Chunks.GetSize();
   for (; i < nCount; i++) {
     nTotal += m_Chunks[i]->nUsed;
     if (nTotal > nIndex) {
       break;
     }
   }
   cp.nChunkIndex = i;
   cp.nCharIndex = m_Chunks[i]->nUsed - (nTotal - nIndex);
 }