Put CJBig2_SymbolDict's images in a CJBig2_List container.

core/src/fxcodec/jbig2/JBig2_SymbolDict.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 "JBig2_SymbolDict.h"
 
 #include "../../../include/fxcrt/fx_memory.h"
 #include "JBig2_Image.h"
 
 CJBig2_SymbolDict::CJBig2_SymbolDict() {
-  SDNUMEXSYMS = 0;
-  SDEXSYMS = NULL;
   m_bContextRetained = FALSE;
   m_gbContext = m_grContext = NULL;
 }
 
+CJBig2_SymbolDict::~CJBig2_SymbolDict() {
+  if (m_bContextRetained) {
+    FX_Free(m_gbContext);
+    FX_Free(m_grContext);
+  }
+}
+
 nonstd::unique_ptr<CJBig2_SymbolDict> CJBig2_SymbolDict::DeepCopy() const {
   nonstd::unique_ptr<CJBig2_SymbolDict> dst;
   const CJBig2_SymbolDict* src = this;
   if (src->m_bContextRetained || src->m_gbContext || src->m_grContext)
     return dst;
 
   dst.reset(new CJBig2_SymbolDict);
-  dst->SDNUMEXSYMS = src->SDNUMEXSYMS;
-  dst->SDEXSYMS = FX_Alloc(CJBig2_Image*, src->SDNUMEXSYMS);
-  for (FX_DWORD i = 0; i < src->SDNUMEXSYMS; ++i) {
-    if (src->SDEXSYMS[i]) {
-      dst->SDEXSYMS[i] = new CJBig2_Image(*(src->SDEXSYMS[i]));
-    } else {
-      dst->SDEXSYMS[i] = NULL;
-    }
+  for (size_t i = 0; i < src->m_SDEXSYMS.size(); ++i) {
+    CJBig2_Image* image = src->m_SDEXSYMS.get(i);
+    dst->m_SDEXSYMS.push_back(image ? new CJBig2_Image(*image) : nullptr);
   }
   return dst;
 }
-
-CJBig2_SymbolDict::~CJBig2_SymbolDict() {
-  if (SDEXSYMS) {
-    for (FX_DWORD i = 0; i < SDNUMEXSYMS; i++) {
-      delete SDEXSYMS[i];
-    }
-    FX_Free(SDEXSYMS);
-  }
-  if (m_bContextRetained) {
-    FX_Free(m_gbContext);
-    FX_Free(m_grContext);
-  }
-}