FPDF_PageDelete must delete XFA pages as well.

fpdfsdk/fpdfxfa/fpdfxfa_doc.cpp

Index: fpdfsdk/fpdfxfa/fpdfxfa_doc.cpp
diff --git a/fpdfsdk/fpdfxfa/fpdfxfa_doc.cpp b/fpdfsdk/fpdfxfa/fpdfxfa_doc.cpp
index 144e5dc811490e751a714994b169d8d91f402a06..6e0edf646eba7d80feed706b3d1293bbc80446a1 100644
--- a/fpdfsdk/fpdfxfa/fpdfxfa_doc.cpp
+++ b/fpdfsdk/fpdfxfa/fpdfxfa_doc.cpp
@@ -182,6 +182,14 @@ CPDFXFA_Page* CPDFXFA_Document::GetPage(IXFA_PageView* pPage) {
   return NULL;
 }
 
+void CPDFXFA_Document::DeletePage(int page_index) {
+  if (page_index < 0 || page_index >= m_XFAPageList.GetSize())
+    return;
+
+  if (CPDFXFA_Page* pPage = m_XFAPageList.GetAt(page_index))
+    pPage->Release();
+}
+
 void CPDFXFA_Document::RemovePage(CPDFXFA_Page* page) {
   m_XFAPageList.SetAt(page->GetPageIndex(), NULL);
 }