Fix wrong page count returned in FPDF_GetPageCount() during loading dynamic XFA files

fpdfsdk/src/fpdfview.cpp

Index: fpdfsdk/src/fpdfview.cpp
diff --git a/fpdfsdk/src/fpdfview.cpp b/fpdfsdk/src/fpdfview.cpp
index 78ef65f0181f6320f8e471e3446e081b36855f48..d008453508487540ef1bebfa8b03edc3c0f2ba2c 100644
--- a/fpdfsdk/src/fpdfview.cpp
+++ b/fpdfsdk/src/fpdfview.cpp
@@ -416,7 +416,7 @@ DLLEXPORT int STDCALL FPDF_GetSecurityHandlerRevision(FPDF_DOCUMENT document) {
 }
 
 DLLEXPORT int STDCALL FPDF_GetPageCount(FPDF_DOCUMENT document) {
-  CPDF_Document* pDoc = CPDFDocumentFromFPDFDocument(document);
+  CPDFXFA_Document* pDoc = static_cast<CPDFXFA_Document*>(document);
   return pDoc ? pDoc->GetPageCount() : 0;
 }