Update CPDF_IndirectObjectHolder APIs for unique objects

fpdfsdk/fpdf_flatten.cpp

Index: fpdfsdk/fpdf_flatten.cpp
diff --git a/fpdfsdk/fpdf_flatten.cpp b/fpdfsdk/fpdf_flatten.cpp
index abfc69b0926d930204ecd995818d61d885f46d5d..3a1135130ecf8e5b1b0a3b665fef8fa6d7f906b4 100644
--- a/fpdfsdk/fpdf_flatten.cpp
+++ b/fpdfsdk/fpdf_flatten.cpp
@@ -186,12 +186,12 @@ CFX_FloatRect CalculateRect(CPDF_RectArray* pRectArray) {
 
 uint32_t NewIndirectContentsStream(const CFX_ByteString& key,
                                    CPDF_Document* pDocument) {
-  CPDF_Stream* pNewContents = new CPDF_Stream(
+  CPDF_Stream* pNewContents = pDocument->AddIndirectStream(
       nullptr, 0, new CPDF_Dictionary(pDocument->GetByteStringPool()));
   CFX_ByteString sStream;
   sStream.Format("q 1 0 0 1 0 0 cm /%s Do Q", key.c_str());
   pNewContents->SetData(sStream.raw_str(), sStream.GetLength());
-  return pDocument->AddIndirectObject(pNewContents);
+  return pNewContents->GetObjNum();
 }
 
 void SetPageContents(const CFX_ByteString& key,
@@ -211,17 +211,15 @@ void SetPageContents(const CFX_ByteString& key,
   }
   pPage->ConvertToIndirectObjectFor("Contents", pDocument);
   if (!pContentsArray) {
-    pContentsArray = new CPDF_Array;
+    pContentsArray = pDocument->AddIndirectArray();
     CPDF_StreamAcc acc;
     acc.LoadAllData(pContentsStream);
     CFX_ByteString sStream = "q\n";
-    CFX_ByteString sBody =
-        CFX_ByteString((const FX_CHAR*)acc.GetData(), acc.GetSize());
+    CFX_ByteString sBody = CFX_ByteString(acc.GetData(), acc.GetSize());
     sStream = sStream + sBody + "\nQ";
     pContentsStream->SetData(sStream.raw_str(), sStream.GetLength());
     pContentsArray->AddReference(pDocument, pContentsStream->GetObjNum());
-    pPage->SetReferenceFor("Contents", pDocument,
-                           pDocument->AddIndirectObject(pContentsArray));
+    pPage->SetReferenceFor("Contents", pDocument, pContentsArray);
   }
   if (!key.IsEmpty()) {
     pContentsArray->AddReference(pDocument,
@@ -318,10 +316,10 @@ DLLEXPORT int STDCALL FPDFPage_Flatten(FPDF_PAGE page, int nFlag) {
     pPageDict->SetFor("Resources", pRes);
   }
 
-  CPDF_Stream* pNewXObject = new CPDF_Stream(
+  CPDF_Stream* pNewXObject = pDocument->AddIndirectStream(
       nullptr, 0, new CPDF_Dictionary(pDocument->GetByteStringPool()));
 
-  uint32_t dwObjNum = pDocument->AddIndirectObject(pNewXObject);
+  uint32_t dwObjNum = pNewXObject->GetObjNum();
   CPDF_Dictionary* pPageXObject = pRes->GetDictFor("XObject");
   if (!pPageXObject) {
     pPageXObject = new CPDF_Dictionary(pDocument->GetByteStringPool());
@@ -426,8 +424,10 @@ DLLEXPORT int STDCALL FPDFPage_Flatten(FPDF_PAGE page, int nFlag) {
 
     CFX_ByteString sFormName;
     sFormName.Format("F%d", i);
+
+    // TODO(tsepez): check |pObj| ownership.
     pXObject->SetReferenceFor(sFormName, pDocument,
-                              pDocument->AddIndirectObject(pObj));
+                              pDocument->AddIndirectObject(UniqueObject(pObj)));
 
     CPDF_StreamAcc acc;
     acc.LoadAllData(pNewXObject);