Re-land "Make CPDF_IndirectObjectHolder use unique_ptr to objects""

core/fpdfapi/fpdf_parser/include/cpdf_object.h

Index: core/fpdfapi/fpdf_parser/include/cpdf_object.h
diff --git a/core/fpdfapi/fpdf_parser/include/cpdf_object.h b/core/fpdfapi/fpdf_parser/include/cpdf_object.h
index 115ce022003b749e0607f2d7fd4c93585b1e71cf..de14503bbbeed7b561cc3c074d171d2f27f02e18 100644
--- a/core/fpdfapi/fpdf_parser/include/cpdf_object.h
+++ b/core/fpdfapi/fpdf_parser/include/cpdf_object.h
@@ -7,6 +7,7 @@
 #ifndef CORE_FPDFAPI_FPDF_PARSER_INCLUDE_CPDF_OBJECT_H_
 #define CORE_FPDFAPI_FPDF_PARSER_INCLUDE_CPDF_OBJECT_H_
 
+#include <memory>
 #include <set>
 
 #include "core/fxcrt/include/fx_string.h"
@@ -92,6 +93,7 @@ class CPDF_Object {
   friend class CPDF_Parser;
   friend class CPDF_Reference;
   friend class CPDF_Stream;
+  friend struct std::default_delete<CPDF_Object>;
 
   CPDF_Object() : m_ObjNum(0), m_GenNum(0) {}
   virtual ~CPDF_Object();