2 files changed, 7 insertions, 1 deletions
diff --git a/core/fpdfapi/page/cpdf_page.h b/core/fpdfapi/page/cpdf_page.h
index 47c5ed94f5..c26c42fc1f 100644
--- a/core/fpdfapi/page/cpdf_page.h
+++ b/core/fpdfapi/page/cpdf_page.h
@@ -10,6 +10,7 @@
 #include <memory>
 
 #include "core/fpdfapi/page/cpdf_pageobjectholder.h"
+#include "core/fpdfapi/parser/cpdf_document.h"
 #include "core/fxcrt/fx_coordinates.h"
 #include "core/fxcrt/fx_system.h"
 #include "core/fxcrt/retain_ptr.h"
@@ -25,7 +26,11 @@ class CPDF_PageRenderContext;
 class CPDF_Page : public CPDF_PageObjectHolder {
  public:
   class View {};  // Caller implements as desired, empty here due to layering.
-  class Extension : public Retainable {};  // XFA page parent class, layering.
+
+  // XFA page parent class, layering.
+  class Extension : public Retainable {
+    virtual CPDF_Document::Extension* GetDocumentExtension() const = 0;
+  };
 
   CPDF_Page(CPDF_Document* pDocument,
             CPDF_Dictionary* pPageDict,
diff --git a/core/fpdfapi/parser/cpdf_document.h b/core/fpdfapi/parser/cpdf_document.h
index 759dd682a6..5ee3c77bb5 100644
--- a/core/fpdfapi/parser/cpdf_document.h
+++ b/core/fpdfapi/parser/cpdf_document.h
@@ -45,6 +45,7 @@ class CPDF_Document : public CPDF_IndirectObjectHolder {
   class Extension {
    public:
     virtual ~Extension() {}
+    virtual CPDF_Document* GetPDFDoc() const = 0;
     virtual int GetPageCount() const = 0;
     virtual void DeletePage(int page_index) = 0;
   };