Fix infinite loop caused by parsing same indirect objects

core/include/fpdfapi/fpdf_parser.h

Index: core/include/fpdfapi/fpdf_parser.h
diff --git a/core/include/fpdfapi/fpdf_parser.h b/core/include/fpdfapi/fpdf_parser.h
index 756850932e5573fcb1f43704fe4cc3364a365db9..e1901ebdcebe4241e814adbf03bbaf6bc26dbaba 100644
--- a/core/include/fpdfapi/fpdf_parser.h
+++ b/core/include/fpdfapi/fpdf_parser.h
@@ -9,6 +9,7 @@
 
 #include <map>
 #include <memory>
+#include <set>
 
 #include "core/include/fpdfapi/fpdf_objects.h"
 #include "core/include/fxcrt/fx_system.h"
@@ -536,6 +537,9 @@ class CPDF_Parser {
   // streams in |m_ObjectStreamMap| are valid.
   std::map<CPDF_StreamAcc*, StreamObjectCache> m_ObjCache;
 
+  // All indirect object numbers that are being parsed.
+  std::set<FX_DWORD> m_ParsingObjNums;
+
   friend class CPDF_Creator;
   friend class CPDF_DataAvail;
 };