[Merge to XFA] Revert "Revert "Add type cast definitions for CPDF_Dictionary.""

core/include/fpdfapi/fpdf_objects.h

Index: core/include/fpdfapi/fpdf_objects.h
diff --git a/core/include/fpdfapi/fpdf_objects.h b/core/include/fpdfapi/fpdf_objects.h
index 58fb37c226b5246366540fd36d0d768edf57e2bb..d64a0924f8a52b15b69f793a70c77761f003ea60 100644
--- a/core/include/fpdfapi/fpdf_objects.h
+++ b/core/include/fpdfapi/fpdf_objects.h
@@ -80,6 +80,11 @@ class CPDF_Object {
 
   FX_BOOL IsModified() const { return FALSE; }
 
+  bool IsDictionary() const { return m_Type == PDFOBJ_DICTIONARY; }
+
+  CPDF_Dictionary* AsDictionary();
+  const CPDF_Dictionary* AsDictionary() const;
+
  protected:
   CPDF_Object(FX_DWORD type) : m_Type(type), m_ObjNum(0), m_GenNum(0) {}
   ~CPDF_Object() {}
@@ -404,6 +409,13 @@ class CPDF_Dictionary : public CPDF_Object {
 
   friend class CPDF_Object;
 };
+inline CPDF_Dictionary* ToDictionary(CPDF_Object* obj) {
+  return obj ? obj->AsDictionary() : nullptr;
+}
+inline const CPDF_Dictionary* ToDictionary(const CPDF_Object* obj) {
+  return obj ? obj->AsDictionary() : nullptr;
+}
+
 class CPDF_Stream : public CPDF_Object {
  public:
   static CPDF_Stream* Create(uint8_t* pData,