FPDF_PageDelete must delete XFA pages as well.

fpdfsdk/include/fpdfxfa/fpdfxfa_doc.h

Index: fpdfsdk/include/fpdfxfa/fpdfxfa_doc.h
diff --git a/fpdfsdk/include/fpdfxfa/fpdfxfa_doc.h b/fpdfsdk/include/fpdfxfa/fpdfxfa_doc.h
index 2bc579c1da3645ce76a54082df6679a0720bbcce..55310e5615fd91bfc19391f04c24129267bc8f17 100644
--- a/fpdfsdk/include/fpdfxfa/fpdfxfa_doc.h
+++ b/fpdfsdk/include/fpdfxfa/fpdfxfa_doc.h
@@ -35,6 +35,8 @@ class CPDFXFA_Document : public IXFA_DocProvider {
   int GetPageCount();
   CPDFXFA_Page* GetPage(int page_index);
   CPDFXFA_Page* GetPage(IXFA_PageView* pPage);
+
+  void DeletePage(int page_index);
   void RemovePage(CPDFXFA_Page* page);
   int GetDocType() { return m_iDocType; }