Make CPDF_Dictionary use unique pointers.

core/fpdfapi/parser/cfdf_document.cpp

Index: core/fpdfapi/parser/cfdf_document.cpp
diff --git a/core/fpdfapi/parser/cfdf_document.cpp b/core/fpdfapi/parser/cfdf_document.cpp
index 0bfcb65df9cbe1a8949c6f1dd71e26c966ce0138..86fc6a8f18449c158489268dfb7ab09399499b87 100644
--- a/core/fpdfapi/parser/cfdf_document.cpp
+++ b/core/fpdfapi/parser/cfdf_document.cpp
@@ -25,8 +25,7 @@ CFDF_Document::~CFDF_Document() {
 CFDF_Document* CFDF_Document::CreateNewDoc() {
   CFDF_Document* pDoc = new CFDF_Document;
   pDoc->m_pRootDict = pDoc->NewIndirect<CPDF_Dictionary>();
-  pDoc->m_pRootDict->SetFor("FDF",
-                            new CPDF_Dictionary(pDoc->GetByteStringPool()));
+  pDoc->m_pRootDict->SetNewFor<CPDF_Dictionary>("FDF");
   return pDoc;
 }