Revert "Update CPDF_IndirectObjectHolder APIs for unique objects."

core/fpdfapi/parser/cpdf_data_avail.cpp

Index: core/fpdfapi/parser/cpdf_data_avail.cpp
diff --git a/core/fpdfapi/parser/cpdf_data_avail.cpp b/core/fpdfapi/parser/cpdf_data_avail.cpp
index 9629c204bbc90c4703dfedeaff100d6e3977bf43..980c94d3250dbe6707ce6663b9a78fc53e0eb7cd 100644
--- a/core/fpdfapi/parser/cpdf_data_avail.cpp
+++ b/core/fpdfapi/parser/cpdf_data_avail.cpp
@@ -1771,9 +1771,8 @@ CPDF_Dictionary* CPDF_DataAvail::GetPage(int index) {
       if (!pPageDict)
         return nullptr;
 
-      // TODO(tsepez): check |pPageDict| ownership.
-      if (!m_pDocument->ReplaceIndirectObjectIfHigherGeneration(
-              dwObjNum, UniqueObject(pPageDict))) {
+      if (!m_pDocument->ReplaceIndirectObjectIfHigherGeneration(dwObjNum,
+                                                                pPageDict)) {
         return nullptr;
       }
       return pPageDict->GetDict();