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

core/fpdfapi/fpdf_edit/fpdf_edit_create.cpp

Index: core/fpdfapi/fpdf_edit/fpdf_edit_create.cpp
diff --git a/core/fpdfapi/fpdf_edit/fpdf_edit_create.cpp b/core/fpdfapi/fpdf_edit/fpdf_edit_create.cpp
index cab99ecf7f5bdefc2e7f502a7b58a098a47cc833..36f622664d78042b09f70d11d86c9f99b494e5f6 100644
--- a/core/fpdfapi/fpdf_edit/fpdf_edit_create.cpp
+++ b/core/fpdfapi/fpdf_edit/fpdf_edit_create.cpp
@@ -1365,7 +1365,7 @@ void CPDF_Creator::InitNewObjNumOffsets() {
   FX_BOOL bNoOriginal = (m_dwFlags & FPDFCREATE_NO_ORIGINAL) != 0;
   for (const auto& pair : *m_pDocument) {
     const uint32_t objnum = pair.first;
-    const CPDF_Object* pObj = pair.second;
+    const CPDF_Object* pObj = pair.second.get();
     if (bIncremental || pObj->GetObjNum() == CPDF_Object::kInvalidObjNum)
       continue;
     if (m_pParser && m_pParser->IsValidObjectNumber(objnum) &&