Fix stack overflow in object Clone() functions

core/fpdfapi/fpdf_parser/cpdf_object.cpp

 // Copyright 2016 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 "core/fpdfapi/fpdf_parser/include/cpdf_object.h"
 
 #include <algorithm>
 
 #include "core/fpdfapi/fpdf_parser/include/cpdf_array.h"
 #include "core/fpdfapi/fpdf_parser/include/cpdf_dictionary.h"
 #include "core/fpdfapi/fpdf_parser/include/cpdf_indirect_object_holder.h"
 #include "core/fpdfapi/fpdf_parser/include/cpdf_parser.h"
 #include "core/fpdfapi/fpdf_parser/include/fpdf_parser_decode.h"
 #include "core/fxcrt/include/fx_string.h"
 #include "third_party/base/stl_util.h"
 
 CPDF_Object::~CPDF_Object() {}
 
 CPDF_Object* CPDF_Object::GetDirect() const {
   return const_cast<CPDF_Object*>(this);
 }
 
+CPDF_Object* CPDF_Object::CloneObjectNonCyclic(bool bDirect) const {
+  std::set<const CPDF_Object*> visited_objs;
+  return CloneNonCyclic(bDirect, &visited_objs);
+}
+
+CPDF_Object* CPDF_Object::CloneDirectObject() const {
+  return CloneObjectNonCyclic(true);
+}
+
+CPDF_Object* CPDF_Object::CloneNonCyclic(
+    bool bDirect,
+    std::set<const CPDF_Object*>* pVisited) const {
+  return Clone();
+}
+
 void CPDF_Object::Release() {
   if (m_ObjNum)
     return;
 
   Destroy();
 }
 
 CFX_ByteString CPDF_Object::GetString() const {
   return CFX_ByteString();
 }
@@ skipping 106 matching lines @@
   return nullptr;
 }
 
 CPDF_String* CPDF_Object::AsString() {
   return nullptr;
 }
 
 const CPDF_String* CPDF_Object::AsString() const {
   return nullptr;
 }